180 BULLETIN" 118, UNITED STATES NATIONAL MUSEUM. 



Agate jasper=intermediate between jasper and chalcedony with predominant trans- 

 lucent chalcedony; jasper with bands of chalcedony. 



Agrite=brown, mottled, calcareous stone. 



Alabandine ruby=red spinel of a violet tint. 



Alabaster=white, fine-grained gypsum; also incorrectly applied to fine-grained and 

 pure-white stalagmites of aragonite. 



Alalite = diopsi de. 



Alaska diamond =quartz. 



Albite=aluminum and sodium silicate (feldspar). 



Albite moonstone=iridescent albite. 



Alencon diamond = quartz crystal from Alencon, France. 



Aleppo stone = eye agate. 



Alexandrite = emerald-green to dark-green chrysoberyl which changes in color to a 

 columbine-red by artificial light. 



Allanite= black hydrous aluminum, magnesium, cerium, and iron silicate and other 

 elements. 



Almandite (almandine)= columbine-red, or a deep crimson and violet garnet, alumi- 

 num and iron silicate. 



Almandine spinel = violet-red spinel. 



Alpine diamond =pyrite. 



Amatrice=green, blue-green, and bluish variscite cut with its associated matrix. 



Amazon stone=green microcline feldspar, aluminum and potassium silicate. 



Amber=fossil resin. 



Amber opal = opal colored brown by iron oxide. 



Amberine=yellowish-green agate from the Death Valley region, California. 



Ambroid=small pieces of inferior amber fused together. 



American jade=californite (vesuvianite). 



American ruby = blood -red garnet, mostly pyrope. 



Amethiste basaltine=pale violet or reddish beryl. 



Amethyst = purple and bluish-violet quartz, in crystals. 



Amethystine quartz = quartz of an amethyst color, not necessarily in crystals. 



Amphibole=group of minerals, aluminum, iron, calcium, magnesium silicates, and 

 silicates of other elements. 



Anatase= titanium oxide. Another name for octahedrite. 



Ancona ruby = quartz. 



Andalusite=aluminum silicate; also trade name for brown tourmaline. 



Andesine=aluminum, sodium, and calcium silicate (feldspar). 



Andradite=garnet, iron and calVium silicate. 



Anthracite=hard iron-black coal, harder than jet or cannel coal. 



A patite= calcium phosphate, with fluorine. 



Aphrizite= black tourmaline. 



Apophyllite= calcium and potassium hydrous silicate. 



Apricotine= yellowish -red quartz pebbles from vicinity of Cape May, New Jersey. 



Aquamarine=light bluish-green or sea-green beryl. 



Aquamarine chrysolite=greenish-yellow beryl. 



Aquamarine topaz =greenish topaz. 



Aragonite = calcium carbonate in orthorhombic crystals. 



Arizona ruby=deep-red pyrope (garnet) from Arizona and Utah. 



Arizona spinel =deep-red pyrope (garnet) from Arizona and Utah. Same as Arizona 

 ruby. 



Arkansas diamond =diamond from Arkansas; also quartz crystals from Arkansas. 



Arkansite= brilliant iron-black, opaque brooldte, oxide of titanium. 



Armenian stone=(in part) lapis lazuli. 



