Smithsonite=carbonate of zinc. In England this carbonate of zinc is called calamine.
Smoky quartz=quartz crystals of a smoky or brown color.
Smoky topaz=true topaz of a smoky color; also more commonly smoky quartz.
Sobrisky opal=opal from the Lead Pipe Spring district in the Death Valley region, Cal.
Sodalite=silieate of aluminum and sodium, with chlorine, generally blue.
Soldier's stone=amethyst. .,
Spanish emerald=emerald of the finest quality (presumably from South America).
Spanish topaz=smoky quartz changed to yellow by heat.
Specular iron ore=hematite.
Spessartite=yellow, brown, or red garnet, silicate of aluminum and manganese.
Sphaerulite=variety of obsidian.
Sphalerite=sulphide of zinc.
of minerals composed of oxides of aluminum, iron, chromium, magnesium,
or zinc. The name spinel is also applied to the species of this group
which consists chiefly of aluminum and magnesium oxides.
Spinel ruby=red spinel.
Spinel sapphire=blue spinel.
Spodumene=silicate of aluminum and lithium.
St. Stephen stone=translucent chalcedony with round blood-red spots through it.
Stalactite=carbonate of calcium in pendent masses deposited in caverns by evaporating water.
Stalagmite=earboniite of calcium deposited from evaporating water on the floors of caverns.
Star stone=starolite (quartz).
Star ruby=ruby (corundum) showing a star of light.
Star sapphire=grayish-blue sapphire (corundum) showing a star of light.
Star topaz=asteriated oriental topaz (yellow corundum).
Staurolite=hydrous silicate of aluminum, iron, and magnesium.
Stibiotantalite=tantalate of antimony.
Succinite=amber; also amber-colored grossularite (garnet).
Sun opal=fire opal.
Sunstone=feldspar (usually oligoclase or labradorite) containing inclusions of minute scales of iron oxide.
Swiss lapis=agate or jasper artificially colored blue.
Synthetic gem=one artificially made from chemicals.
Syrian garnet=almandite (garnet) of a violet shade.
Tabasheer=amorphous opal-like silica deposited in the joints of bamboo.
Tauridan topaz=very pale blue topaz.
Taxoite=serpentine from Chester County, Pa.
Test stone=basanite (jasper).
Texas agate=agate jasper from Texas.
Thetis hairstone=transparent quartz with inclusions of hairlike crystals of green actinolite.
Thomsonite=zeolite, hydrous silicate of aluminum, calcium, and sodium.
Tiger-eye=yellow to brown, altered crocidolite.
Titanite=silicate of calcium and titanium.
Toad's-eye tin=concentric cassiterite. Same as'wood tin but on a smaller scale.
of aluminum, with fluorine. Most of the ordinary topaz of commerce is "
false topaz " or yellow to brown quartz. Much of the " yellow quartz "
is smoky quartz artificially changed from brown to yellow by heat. The
term topaz is also improperly applied to any yellow stone.
Topaz cat's-eye=yellow corundum showing an elongated or round patch of opalescent light.