Safety Chain
A safety chain is a secondary closure (usually on a fine bracelet or watch) that is used in case the primary clasp opens, preventing the loss of the bracelet. It is usually a chain that is permanently attached to one side of the bracelet, and attaches to the other side with a spring ring clasp (or other type of clasp). On the Miriam Haskell cuff bracelet above, the safety chain is located on the lower left of the picture.

Safety Clasp
A safety clasp is a secure type of closure on a piece of jewelry. The term safety catch is used for a variety of these closures. On pins and brooches, a safety clasp often refers to a long pin on a hinge that can be held or released with a secure clasp (often a rotating circle within a circle).

Salt
A colorless or white crystalline solid, composed of sodium chloride. It is found native in the earth, and is also produced by the evaporation and crystallization of sea water and other water impregnated with saline particles. Salt is used extensively in ground or granulated form as a food seasoning and preservative.

San Marco Chain
A unique kind of chain wherein each link is long and rounded, resembling a puffed grain of rice with a flat bottom. The links are arranged next to each other at a 45 degree angle and attached to each other on the bottom by sturdy flat pins set at an opposite angle.

Sand Casting
For hundreds of years sand casting was the most popular of all casting methods. It still plays an important role in the production of large metal forms, (typically Iron, but also Bronze, Brass, Aluminum). Tempered sand is packed onto wood or metal pattern halves, removed from the pattern, and metal is poured into resultant cavities. Molds are broken to remove castings.

Sandor
Sandor was a small costume jewelry company founded by Sandor Goldberger. Sandor jewelry often has delicate floral designs with enameling and rhinestones. The Sandor company was in operation from the 1939 until the 1970's.

Sandstone
Just as the name implies, sandstone is a sedimentary stone made of sand that has been fused with some cementing element like clay or quartz.

Sapphire
A precious gemstone (a type of corundum) that ranges in color from blue to pink to yellow to green to white to purple (mauve sapphire) to pink-orange (padparadscha sapphire). Six-sided asterisms sometimes occur in star sapphires (caused by inclusions of tiny, thin, parallel needles of rutile). Sapphires are related to rubies. Sapphires were once thought to protect the wearer from poisonous creatures. Sapphire has a hardness of 9 and a specific gravity of 3.9 - 4.1. Sapphires are often heat treated to improve their color.

Sapphire Quartz
Sapphire quartz (also called blue quartz) is another name for blue chalcedony.

Sarah Coventry
A company that produced mid-range costume jewelry. The Sarah Coventry jewelry company was founded in Newark, New Jersey, USA, by Charles H. Stuart in November, 1948 (Stuart had founded the Emmons jewelry company earlier). He named the company after his granddaughter Sarah. Sarah Coventry jewelry was sold at home fashion shows until 1984, when the company was sold. Both women's and men's jewelry was produced under the marks Sarah Coventry (first used in May 1949), SC (first used in Oct. 1953), Sarah Cov (first used in Jan. 1960). Sarah Coventry jewelry came with a "Lifetime Guarantee" which read, "May be sent back for repair to: P.O. Box 7899, Warwick, RI 02887. Please include handling charge of 1.50."

Sard
A semi-precious stone related to carnelian. This brownish-red, opaque gemstone was once used extensively for seals and was carved using intaglio. Sard was named for Sardis, the ancient capital of Lydia. Sardius is mentioned in the Bible, and may refer to jasper.

Sardonyx
A semi-precious stone that is formed by two layers, a red-brown layer of sard and a gray, white, black or brown layer of onyx. Sardonyx is a type of quartz. Sardonyx is frequently carved to make intricate cameos and seals.

Satin Finish
A satin finish on a metal is between a matte finish and a brilliant one. This semi-glossy finish is done by making shallow parallel lines on the surface of the metal, reducing its reflectivity.

Saturation
A measure of the intensity of color inherent in a gemstone. Stones that are well saturated with color are more valuable.

Sautoir
A sautoir (also known as a rope) is a long necklace (longer than opera-length), often with an ornament (a tassel or pendant) at the end. Sautoirs were common during the Edwardian era.

Scalenohedral
A fancy shape gemstone made up of 12 facets, each shaped like a scalene triangle. Crystal points with triangular facets are said to be scalenohedral.

Scalloped
An ornamental border consisting of a series of curved projections.

Scarab
A scarab is a type of beetle. The ancient Egyptians used stones carved in the shape of scarabs extensively in their jewelry and other decorations. In the 1920s, after the tomb of King Tut was discovered in Egypt, Egyptian style jewelry became fashionable in the West, including scarab braclets and necklaces.

Scarabé
A type of iridescent finish applied to some dark glass beads. The scarabé finish mimics the look of iridescent scarab beetles.

Scatter Pins
Scatter pins are small pins that are worn together in small groups.

Scepter
A symbol of spiritual and worldly power used as a part of royal insignia. A scepter is really nothing more than a simple staff, but the ones used in ceremony are usually highly decorated with precious metals and gemstones. The topping of a scepter varied in different countries and in different periods. In the Middle Ages two forms were distinguished: a long staff (baculum), otherwise called rod, and a short one (sceptrum), although their meaning was identical. The long staff, topped with a globe, is a typical attribute of God in Carolingian painting. A scepter could be crowned with three leaves or a lily, a globe, a bird, etc.

Schiaparelli, Elsa
Elsa Schiaparelli was a fashion and jewelry designer. Schiaparelli jewelry is avidly collected. The understated Schiaparelli earrings above are made of a silver-colored metal.

Schiller
Schiller (from the German term for play of colors or glitter) is an iridescent or bronze-like luster occuring in some minerals (it is also referred to as labradorescence when it occurs in feldspars). This optical effect is caused by submicroscopic lamella (thin layers or flakes of inclusions) contained within the mineral. These layers of inclusions can produce a bronze-like luster, golden iridescence, red color-play, and/or a blue-green sheen that flashes when viewed from certain angles. This type of inclusion can be valuable (as in sunstone and labradorite). Layers of shiller can block reflected light, decreasing the stone's brightness. Some types of feldspars (like labradorite, sunstone, spectrolite and peristerite) and other minerals (like hypersthene) exhibit schiller.

Schorl
Black Tourmaline.

Screw Back
A type of earring attachment for non-pierced ears where the earring is tightened against the earlobe by means of a screw with a flat padded end.

Scrimshaw
A type of folk art dating from at least the 17th century in which whale teeth, whale bones and walrus tusks are engraved or lightly carved with a picture or design. It was a way for sailors on long whaling voyages to pass time but has become very collectible.

Sea Glass
Sea glass (also called beach glass) is glass from old broken bottles, windows of wrecked ships, etc. that has been worn down and etched by the sea and sand over the years. This glass is smooth (with no sharp edges) and looks like beautifully sand-blasted glass with a soft patina. Pieces of this glass are collected on beaches and often made into jewelry items. Brown, deep green and clear are the most common colors of sea glass; after these come blue, amber and aqua. Rare colors include pink, red, purple, light yellow, and sea green.

Seal
Seals were once extensively used as a means of identification; they were only owned and used by relatively important people. Seals were usually mounted in rings or hung on a chain. Seals are carved in hard stones (like sard or jasper) using intaglio.

Seashell
Any of a number of shells of marine creatures such as mollusks or gastropods which can be used as jewelry. See cowrie shell, olivelia shell, abalone, ammolite, etc.

Sedimentary
Rock formed by layers of material that has accumulated and hardened over time.

Seed Bead
Mass produced tiny glass or plastic beads made by slicing tubes into tiny evenly spaced pieces. This makes them oblong in shape, rather than round, and flat on the ends. Seed beads can be strung together to make a necklace or bracelet, but are commonly used as spacers for larger beads. They can also be strung on a loom to make beaded bands and belts.

Seed Pearls
Seed pearls are tiny, round pearls that are less than 2 mm in diameter and weigh under 1/4 grain. Seed pearl jewelry was popular from the mid- to late-Victorian era, when the tiny pearls were strung on horsehair to form intricate designs and were also used as accents on other jewelry.

Seftonite
Seftonite is a translucent, moss green type of chalcedony. It is found in South Africa and North America.

Selenite
A soft, colorless-to-slightly-colored, transparent mineral. It is a crystalline variety of gypsum. Selenite has a hardness of 1-2 and a specific gravity of 2.3 to 2.4.

Selini
Selini was a costume jewelry company whose mark appears from the 1930s to the 1950s. Selini jewelry is usually intricate, well-designed, and often decorated with colored rhinestones and enamel. Very little is known about the company (If you have any information about the history of the company or the Selini mark, please email me).

Semi-Mount/Semi-Mounting
A finished piece of jewelry already embellished with gemstones and/or engraving that is simply waiting for the center stone. Pieces are sold this way to allow the buyer to add a center stone of their own choosing.

Semiprecious
Any gemstones valued for their beauty but which are not one of the four "precious stones", (emerald, diamond, ruby or sapphire). Some examples of semiprecious stones are amethyst, aventurine, carnelian, garnet, opal, peridot, rose quartz, etc.

Semiprecious Gemstone
Any stone that is not classified as precious . Some examples are: turquoise, aquamarine, agate, jade, pearl, rose quartz, aventurine.

Serpentine
Serpentine is a green stone; there are two types of serpentine, bowenite and hydrated magnesium silicate. Bowenite is a jade-like stone (green to black) that is sometimes used in jewelry. The softer variety, hydrated magnesium silicate, is translucent serpentine has a hardness of 4 () - 5.5 (bowenite) and a specific gravity of 2.5 to 2.6. Serpentine is found in the British Isles and some other locations. Connemara marble (from Ireland) is a type of cloudy green serpentine.

Serpentine Chain
A series of small, flat, s-shaped links set very closely together and held in place by a second set of small, flat, s-shaped links set very closely together underneath them.

Setting
A setting is a method of securing a stone (or other ornament) in a piece of jewelry (or other object). There are many different types of settings, including the collet (a strip of metal surrounding the stone), the claw setting (in which prongs of metal hold the stone in place), Tiffany (a high,six-pronged setting), the cut-down setting (metal is worked around the edge of the gem, reinforced with metal ridges), pavé-set stones (stones set close together, showing no metal between them), millegrain (the stone is secured by small beads [grains] of metal), gipsy setting (with a recessed stone), and many other types (including combinations of the above-mentioned methods). Some settings are closed (there is metal behind the stone), while others are open (there is no metal behind the stone), letting light shine through the stone.

S. G.
S.G. (or s.g.) is an abbreviation for specific gravity, a comparison of a material's weight with the weight of an equal volume of water.

Shank
The shank is the part of a ring that encircles the finger.

Shekel
A Hebrew unit equal to about a half ounce. A common estimate makes the shekel equal in weight to about 130 grains for gold, 224 grains for silver, and 450 grains for copper. A shekel is also a gold or silver coin equal in weight to one of these units, especially the chief silver coin of the ancient Hebrews. The approximate values of the coins are (gold) $5.00, (silver) 60 cents, and (copper half shekel), one and one half cents.

Sherman
Sherman was a Canadian costume jewelry company that produced very high-quality pieces. Colorful or clear prong-set rhinestones or cut crystal beads (sometimes with an aurora borealis finish) adorn most Sherman pieces; the metal is rhodium-plated or gold-plated. "Jewels of Elegance" by Sherman was written on some carded Sherman jewelry. Sherman produced jewelry from 1947-1981.

Shiller
Shiller is a mispelling of schiller.

Shoulder
The part of a ring between the shank and the center of the setting.

Signet
A carved design, like an intaglio, which was usually worn on a ring. It was pressed into soft wax to authenticate a document. The design was usually a coat of arms, family crest, or some other type of insignia or monogram unique to the person using it.

Signet Ring
A signet ring is a ring that was used as a means of identification for relatively important people. The signet ring was engraved with a symbol (a coat of arms or initials) identifying a particular person. Some signet rings also had intaglio-carved seals. The earliest-known signet rings date from ancient Egypt, thousands of years ago.

Silicate
Any of a large group of minerals, forming over 90 percent of the earth's crust, that consist of silicon, oxygen, and one or more metals, (and sometimes hydrogen).

Silicon
A nonmetallic element which is only found as a compound with other elements in nature. When artificially extracted, silicon appears as a dark brown amorphous powder, or as a dark crystalline substance with a metallic luster. This substance is used in combination with other materials in glass, semiconducting devices, concrete, brick, refractories, pottery, and silicones. Its oxide is silica, or common quartz, and in this form, or as silicates, it is the second most abundant element in the Earth's crust, next to oxygen, making up 25.7% of it by weight.

Silky
The luster of a gemstone having a smooth, gleaming surface similar to silk or long silky fur. Tiger's eye exhibits a silky luster.

Sillimanite
Sillimanite (aluminum silicate, Al2 SiO5) is a transparent to translucent mineral that ranges in color from white to gray to brownish to greenish. Sillimanite has the same chemical formula as both kyanite and andalusite (these three minerals are polymorphs); Sillimanite is the rarest of the three (all three are used in high-temperature ceramics, used in spark plugs). Sillimanite has a hardness of 7.5 and a specific gravity of 3.2. Sillimanite is the state mineral of Delaware (since March 24, 1977); SIllimanite is found near near Wilmington, Delaware. Sillimanite is found in Brazil, New England (USA), and Europe; it is found in areas of high-grade metamorphic rock.

Silver
Silver is a fine, silver-white metal often used in jewelry. Pure silver has a hardness of 2.5. Other metals are alloyed with silver (usually copper) for silver used in jewelry making. Silver tarnishes after exposure to air (a thin layer of silver-oxide forms on the surface). Silver often occurs near copper lodes.

Silver 800
Silver 800 is silver with a fineness of 800, that is, it contains 800 parts per thousand (or 80 percent) silver and 200 parts per thousand (or 20 percent) copper. Silver 800 is used for casting.

Singapore Chain
A style of chain wherein each link is composed of a series of flat, diamond-cut, interwoven concentric loops.

Single-Cut Diamonds
Genuine diamonds, commonly used in watchcases, that contain only 18 facets.

Silver Tone
Jewelry finished with a silver color with very little appreciable measurement of weight in silver.

Silvery Finish
Jewelry that has the look of silver but no actual silver content.

Simulated Stones
Any natural or synthetic substance which is meant to resemble a gemstone. cubic zirconia, for example, is a simulated diamond.

Simulated Tortoise
A synthetic material resembling the mottled brown and yellow color found on tortoise shells.

Slab
A slab is a broad, flat, relatively thin piece of stone cut from a larger chunk of stone. Lapidaries use slabs when cutting cabochons or material for jewelry inlay work.

Slate
A smooth, solid gray fine-grained rock that can be split into thin layers.

Sleeper
A sleeper is a small hoop-earring made of gold that is used to keep the hole in a pierced ear open.

Sliced
A bracelet that is the same thickness all the way around and does not taper at the edges; as though it were simply sliced off the end of a cylinder.

Slide
An ornament with a tube on the back. A cord or necklace can then be threaded through the tube allowing the ornament to slide along the length of the cord or necklace. See Bolo.

Slide Bracelet
(also called slide charm bracelet) A slide bracelet is a type of modern-day charm bracelet made from stringing Victorian era watch fob charms together on a double chain - the charms can slide along the chains. When pocket watches (used by men) and nceklace watches (used by women) went out of style after wrist watches were invented, the charms on the watch chain were removed and then strung together to make bracelets. Modern imitations are made using modern-manufactured charms.

Smoky Quartz
Smoky quartz is a type of brownish quartz that has a smoky look.

Smoky Topaz
see Smoky Quartz.

Snake Chain
A snake chain (also called a Brazilian chain) is a metal chain made up of a series of small, linked cups.

Snap Bar Closure
The hinged bar on the back of a lever back or omega back earring.

Snowflake Obsidian
Snowflake Obsidian (also called flowering obsidian) is a volcanic glass that is usually dark (black or brownish) with white "snowflakes". This glassy, lustrous mineral is found in lava flows, and obsidian stones can be massive. Obsidian is formed when viscous lava (from volcanos) cools rapidly. Most obsidian is 70 percent silica. Obsidian has a hardness of 5 and a specific gravity of 2.35.

Soapstone
Soapstone (also called steatite) is a soft, easily-carved, fine-grained metamorphic rock that can be green, brown, or gray. This stone has a greasy, soapy feel to it, hence its name. Soapstone is found worldwide. It is carved into figurines, beads, seals, bowls, pipes, cookware, and other items - it has been used since ancient times. Chemically, soapstone is composed mostly of talc, hydrated magnesium silicate (Mg3Si4 O10(OH)2) plus other minerals. Soapstone has a hardness of 1-1.5 (extremely soft - it can be scratched with a fingernail) and a specific gravity of 2.2-2.8.

Soda
Any of various forms of sodium carbonate used in making soap, powders, glass, and paper.

Sodalite
Sodalite is a dark blue mineral with streaks of white, gray, pink, or green. It is used for carvings and jewelry. Sodalite is one of the mineral components of lapis lazuli. . Sodalite is sodium aluminum silicate chloride; its formula is Na4Al3(SiO4)3Cl. Sodalite has a hardness of 5.5 to 6 and a specific gravity of 2.1 - 2.3. Sodalite is found in Brazil, Canada, India, Italy, Namibia, United States, and Russia.

Sodium
A common soft, waxy, light, extremely malleable silver-white unstable metallic element of the alkali group. It is always found as a compound with other elements in nature, such as common salt, albite, etc. Sodium burns with a yellow flame, and is so readily oxidized that it combines violently with water and to be preserved must be kept under petroleum or some similar liquid.

Solder
Solder is a metal alloy (a mixture of metals) thatis used to join other metals. Solders melt at a lower temperature than the metals to be joined.

Soldering
A technique used in making and repairing jewelry whereby two pieces of metal are joined by applying a molten metal which has a lower melting point than the two metals being joined.

Solitaire
A solitaire is a ring set with a single stone, usually a diamond.

Sorrelli
Sorrelli (the Italian word for "sisters") Jewelry of Kutztown, Pennsylvania, was formed in 1983 by Lisa Oswald and her twin sisters Susie and Sandy. Sorrelli's high-quality, hand-made jewelry features Swarovski Austrian rhinestones and semi-precious stones.

Souvenir Jewelry
Souvenir jewelry is made for tourists as a remembrance of their trip. The mother-of-pearl Eiffel Tower pin above is a souvenir of Paris.

SPARKLE
A measure of the light reflected out by a diamond or stone as it is viewed from different angles.

Specific Gravity
The specific gravity (abbreviated s.g.) of a material is a comparison of its weight with the weight of an equal volume of water. Specific gravity measures the density of a material.

Spectrolite
Spectrolite is another name for Finnish Labradorite (a variety of plagioclase feldspar). It is a fairly abundant grayish mineral that has brilliant iridescent flashes of color (usually green, blue, orange, or red) after it is polished. The crystals are transparent to translucent. Spectrolite is usually cut with a flat surface in order to highlight the brilliant flashes of color. Spectrolite has a hardness of 6 to 6.5 and a specific gravity of 2.70.

Spectroscope
A spectroscope is an instrument that is used to identify gemstones. It works by determining the light waves that a stone absorbs; different stones absorb different wavelengths of light.

Spessartine Garnet
Spessartine garnet (also called Spessartite garnet) is a type of a garnet that is orange (it varies from reddish orange to brownish orange to yellowish orange). The chemical composition is Manganese Aluminum Silicate. Crystals vary from transparent to translucent. This relatively rare gem is found in Sri Lanka, Australia, Madagascar, Brazil, Sweden, Myanmar, and the U.S. Spessartine garnet has a hardness of 7.0 - 7.5, a specific gravity of 4.19 (relatively heavy), and a refractive index of 1.8.

Spessartite
A red to brownish-red garnet composed of alumina manganese.

Sphene
Sphene (sometimes called titanite) is a mineral that comes in green, yellow, white, brown or black wedge-shaped crystals (sphene means wedge in Greek). Sphene is used only rarely as a gem (due to its relative softness). It's chemical formula is CaTiSiO5, Calcium Titanium Silicate. Sphene has a hardness of 5-5.5, a specific gravity of 3.3 - 3.6, and a white streak.

Spinel
Spinel is a very hard semi-precious stone composed of octahedral crystals. Spinel ranges in color from red to black to yellow, frequently resembling rubies. Iron and chrome are components of spinel, giving it its color. Spinel belongs to the feldspar species and is found in in Burma, Sri Lanka and Thailand. Some varieties include: Balas ruby (red spinel), Almandine spinel (purple-red), Rubicelle (orange), Sapphire spinel (blue), Ghanospinel (blue), Chlorspinel (green). Spinel is also laboratory synthesized. Spinel has a hardness of 8, a specific gravity of 3.58-4.06, and a refractive index of 1.72.

Split Ring
A tightly-coiled ring used as an jewelry finding; it can attach charms to a charm bracelet or a clasp to a necklace or bracelet (it is like a miniature version of a keychain).

Spray Brooch
A type of brooch, usually worn at the shoulder, which is characterized by floral themes featuring long stemmed jeweled flowers and long leaves.

Spring Ring
A spring ring (also known as a bolt ring) is a hollow circular metal fastening ring with a spring opening. A tiny spring keeps the arm of this clasp closed. It is used to attach two other rings or links of a necklace or bracelet. The spring ring was invented early in the 1900's. Jewelry made prior to 1900 or so will not have a spring ring clasp.

Spring Ring Clasp
A very common kind of clasp used for joining two ends of a necklace. The clasp itself consists of a hollow metal tube in a circle shape with a gap in the side. The hollow tube contains a small wire held in place by a spring inside the tube behind the wire. The wire can be pulled back by means of a small knob which slides along the outer edge of the circular tube. Releasing the knob allows the spring to push the wire forward closing the gap. The other end of the necklace terminates in a small ring. By using the knob on the spring ring to open the gap in the hollow circular tube, one can then place the small ring through the gap and close the wire through the ring securing it in place and closing the necklace.

Square Cut
A style of gem cutting resembling the emerald cut.

Square Setting
A square shaped setting with a prong at each corner.

Squarillion Cut (SQUARE CUT)
A Squarillion cut is a square-cut stone. This fancy cut is relatively new and is also known as a Princess or Quadrillion cut.

Squash Blossom Necklace
A traditional piece of Navajo jewelry based on an old and favored Spanish-Mexican ornament which was actually not a squash, but a stylized version of the pomegranate. A shape that the Spanish Conquistadores used as buttons on their trousers. The squash blossom necklace is composed of beads resembling squash blossoms placed at regular intervals with a naja, (crescent shaped pendant), at the center.

SS
SS is an abbreviation for sterling silver.

Stabilized Stones
Stabilized stones have been impregnated with plastic to improve its durability, stabilize cracks, and improve the stone's appearance (a dye is sometimes added to the plastic - this is called a color shot or color stabilized). Liquid plastic resins are injected into soft, porous stone at high pressures - the plastic fills the pores in the stone. Turquoise is often stabilized.

Stabilized Turquoise
Turquoise is very porous by nature which allows it to absorb any pollutants that it comes in contact with, including oils from the skin. Stabilized turquoise has been treated by various methods to reduce the porosity, thus making less changeable over time.

Stack Rings
Two or more rings that are designed to be stacked on the same finger at the same time.

Stainless Steel
An extremely durable alloy of steel and chromium which can be polished to resemble a precious metal and is virtually immune to rust, discoloration and corrosion.

STAMPING
Using a punch or die to cut or emboss a sheet of metal with a mark.

STAR
The Star Company of Houston, Texas, manufactured costume jewelry beginning before 1930. Pieces often include thermoset plastic "jewels."

STAR OF AFRICA
The Star of Africa (also called the Cullinan diamond) is the largest diamond yet found, weighing 3,106 carats (roughly 1.3 pounds) in its rough form. It was mined at the Premier Mine in South Africa in 1905. This enormous gem was named for the chairman of the company that owned the mine. It was given to King Edward VII of England for his birthday in 1907. The diamond was cut (by Joseph J. Asscher of Amsterdam) into many stones, including the Cullinan I (530 carats, pendelique-brilliant shaped, the largest cut diamond in the world), the Cullinan II (317 carats, cushion shaped), Cullinan III (94 carats, pendelique shaped), Cullinan IV (63 carats, square-brilliant shaped), and many other smaller stones.

STAR GARNET
A "star garnet" is almandine that exhibits an asterism. Almandine is a type of garnet that ranges in color from deep red to reddish-brown.

STAR OF INDIA
The Star of India is a huge, blue, star sapphire weighing 563.35 carats. It is cut as a cabochon. This gemstone was found in Sri Lanka (date unknown). A British Army officer brought it to London, where it was cut by Albert Ramsay around 1905. It is now at American Museum of Natural History.

STAR OF THE SOUTH
The Star of the South is a the largest diamond found in South America. This Brazilian stone weighs 254.5 carats.

STAR RUBY
A "star ruby" is a ruby that exhibits an asterism, a six-pointed star of light (when cut as a cabochon). The world's biggest star ruby is the Rajaratna, which weighs 2,475 carats. The world's biggest double-star ruby (with a 12-pointed star) is the Neelanjali, weighing 1,370 carats. Most star rubies today are synthetic.

STAR SAPPHIRE
A star sapphire is a sapphire that exhibits an asterism in the form of a colorless, six-rayed star that reflects light. Star sapphires are cabochon cut. Laboratory-produced star sapphires ("Linde stars") were developed in 1947 by the Linde company; most star sapphires today are synthetic.

STAR SETTING
A star setting is one in which a gem is set within an engraved star; the gem is secured by a small grain of metal soldered tp the base of each ray of the star. This type of setting was popular in the 1890s.

STATER
A silver coin from ancient Greece.

STEATITE
Steatite (also called soapstone) is a soft, easily-carved, fine-grained metamorphic rock that can be green, brown, or gray. This stone has a greasy, soapy feel to it, hence its name. Soapstone is found worldwide. It is carved into figurines, beads, seals, bowls, pipes, cookware, and other items - it has been used since ancient times. Chemically, soapstone is composed mostly of talc, hydrated magnesium silicate (Mg3Si4 O10(OH)2) plus other minerals. Soapstone has a hardness of 1-1.5 (extremely soft - it can be scratched with a fingernail) and a specific gravity of 2.2-2.8.

STEP CUT
The step cut is generally used for colored stones. This cut is rectangular to square and has many facets parallel to the edges of the stone.

STERLING
Sterling is silver with a fineness of 925, that is, sterling is 925 parts per thousand (or 92.5%) silver and 75 parts per thousand (or 7.5%) copper (the copper increases the silver's hardness). Sterling is quite malleable.The pin pictured above is a rhinestone-studded sterling bow made by Trifari.

STERLING SILVER
Sterling is silver with a fineness of 925 parts per thousand or 92.5% silver and 75 parts per thousand or 7.5% copper. Copper is added to the alloy to increase the silver's hardness.

STICK PIN
A pin with an ornament on the top worn vertically on a scarf, tie, or lapel. Also called a "tie pin" or "lapel pin"

STIPPLED FINISH
A texture formed by a series of pricks made with a steel punch.

STRASS
Strass is highly reflective glass that is made to imitate gemstones. The original rhinestones were quartz stones obtained from the Rhine river. These stones were cut to resemble gemstones.

STREAK
The streak of a mineral is its color when it is in powdered form. You can determine the streak of a mineral easily by rubbing a rough mineral (not cut stones!) along the surface of a hard, unglazed porcelain sheet (this is called a streak plate - you can use the back of a white porcelain bathroom tile). Even though the color of a mineral may vary, the streak color is constant. Note: the streak plate has a hardness of about 6.6, so it can only test mineral that less hard than that (since they must leave a streak on the porcelain). For example, the streak of chalcopyrite, graphite, magnetite, and pyrite is black, the streak of galena is gray, the streak of cinnabar, the streak of azurite and lapis is blue, the streak of malachite is green, the streak of turquoise is white with a green tint, the streak of olivine, amethyst, and tourmaline is white, and the streak of hematite is red-brown.

STRIATIONS
Striations are grooves, lines and scratches found naturally in some minerals.

STRONGWATER, JAY
Jay Strongwater is a New York company that produces metal decorative objects (like picture frames, boxes, clocks, candle holders, napkin rings, coasters, vases, bottle stoppers, compacts, Christmas tree ornaments, etc.) that are elaborately decorated with enamel work and Swarovski rhinestones. These elegant pieces often use themes from nature (like leaves, flowers, and/or animals) or Perisan designs. Jay Strongwater designs a line of these upscale accessories for Oscar de la Renta. Jay Strongwater was created by Jay Feinberg, who began his career designing jewelry under his own name, but later named his company Jay Strongwater (using his mother's maiden name).

STUD
A simple style of earring for pierced ears that has a single stone (such as a pearl) or metal ball on a straight post with no dangling parts. (See also Button earring).

SUGAR BEADS
Sugar beads are beads that look as though they were rolled in granulated sugar; the fine grains on the surface of the beads are in fact tiny grains of glass (or plastic). Delicate glass sugar beads were made in Gablonz and Japan early in the 20th century.

SUGILITE
Sugilite is a medium to dark purple semi-precious gemstone (it can also range from pink to brown to black). It is usually opaque with a waxy luster (but can be translucent) and often has brown, pink and white inclusions, looking like a purple version of turquoise. It is usually polished and not faceted. Sugilite has a hardness of 5.5-6.5 and a specific gravity of 2.75 - 2.80. This stone is not enhanced - massive stones are often found. Sugilite is Potassium Sodium Lithium Iron Manganese Aluminum Silicate; its formula is KNa2Li3(Fe, Mn, Al)2Si12O30. This stone was named for Ken-ichi Sugi, the Japanese geologist who discovered it in 1944. It is found in Iwagi Island, Shikoku, Japan and Mont Saint-Hilaire, Quebec, Canada, but the largest deposits are in northern South Africa.

SULFATE
A salt containing sulfur dioxide.

SULFUR
An abundant, pale yellow, nonmetallic element used in black gunpowder, rubber vulcanization, the manufacture of insecticides and pharmaceuticals, and in the preparation of sulfur compounds such as hydrogen sulfide and sulfuric acid.

SULPHUR
A variant spelling of sulfur.

SUNSTONE
Sunstone is also called aventurine feldspar (a variety of oligoclase). This gemstone varies from golden to orange to red-brown, and can be transparent or translucent. Sunstone is metallic-looking due to sparkling red, orange or green crystalline inclusions (these are hematite or goethite crystals). Sunstone is found in Canada, the USA (in Oregon), India, Norway, and Russia. This brittle stone has a hardness of 6 and a specific gravity of 2.63 - 2.67. Sunstone is not enhanced.

SWAROVSKI
Swarovski is an Austrian company that makes high-quality rhinestones, beautiful cut crystals, costume jewelry, and other glass-related items. The company was founded by Daniel Swarovski (1862-1956), the son of a glass faceter. In 1892, Daniel developed a new mechanized technique for faceting glass crystals, creating a sparkling, diamond-like "chaton." He then started a factory (and company) in Wattens, Austria (in the Tyrolean Alps) in 1895. In the 1970's, the company expanded to the Providence, Rhode Island, USA - they later moved to Cranston, Rhode Island. In 1955, Swarovski and Christian Dior developed the iridescent aurora borealis stone. The company began a line of rhinestone costume jewelry in 1977. Since 1988, the Swarovski logo has been a swan (before 1988, the logo was an edelweiss flower).

SWISS LAPIS
Swiss lapis is not lapis lazuli at all. It is jasper dyed to resemble lapis lazuli and is misleadingly called "Swiss lapis."

SWOBODA
Swoboda makes high-quality costume jewelry using gold-plated metal and semi-precious stones (like carved jade and cultured pearls). This California company uses unusual designs and pieces are often figural.

SYMMETALIC
Symmetallic is a mark used by the W. E. Richards Company of North Attleboro, Massachusetts, USA. This company made very good quality silver, gold-plated silver, and low-carat gold jewelry. Pieces often havae cultured pearls, moonstones, and other semi-precious stones. The mark SYMMETALIC was first used in December, 1936.

Symmerty
How similar one side of an object is to the other side. The lengths and angles on each side of a faceted gemstone are closely compared. The more uniform the cut, the higher the value of the stone.

Synthetic
Gemstones produced in a laboratory rather than found in nature. Synthetic gemstones are not "fake", since they have exactly the same chemical characteristics as the natural stone, but they are usually flawless and much cheaper than the real thing. The most common synthetic gems are emeralds, rubies, sapphires and opals.

Synthetic rubies
Synthetic rubies were first made by the French chemist Auguste Verneuil, who invented the flame-fusion process for producing inexpensive rubies in 1886. It was a ruby, but it didn't look much like one. In 1918, J. Czochralski invented the pulling method for growing inexpensive rubies. Carroll Chatham synthetic rubies (more expensive to produce, but natural-looking) were introduced in 1959. Kashan synthetic rubies were made beginning in 1979.

Synthetic Stones
Synthetic stones are made in laboratories; these stones generally lack imperfections. It is very difficult to distinguish a synthetic stone from a natural stone.

Synthetic Turquoise
A man made chemical identical with that of the natural stone.