CATALOGUE OF GEMS AND PRECIOUS STONES. 181 



Arrow points=Indian arrowheads mostly made of quartz, more rarely of obsidian or 



other fine-grained rock. 

 Asparagus stone=pale-yellow apatite. 



Asteria=asteriated sapphire; also any gem showing a six-ray star when cut cabochon. 

 Asteriated topaz =asteriated oriental topaz (yellow corundum). 

 Australian sapphire=deep inky blue sapphire (corundum). 

 Automolite= dark-green to nearly black zinc spinel. 

 Aventurine=opaque yellow, brown, or red massive quartz containing inclusions of 



minute scales of some other mineral, such as mica or iron oxide. 

 Aventurine feldspar=sunstone. 

 Axstone = nephrite. 



Axinite=aluminum, calcium, iron, and manganese hydrous borosilicate. 

 Aztec stone =chalchihuitl. 

 Azure quartz =blue quartz. 

 Azure stone=lapis lazuli. 

 Azulite=pale-blue smithsonite. 

 Azurite=blue, copper hydrous carbonate. 

 Azurite malachite=azurmalachite. 

 Azurmalachite=combination of the copper carbonates azurite (blue) and malachite 



(green) from the copper mines of Arizona. 



B. 

 Baffa diamond = quartz crystal. 

 Bahias= diamonds from Bahia, Brazil. 

 Balas ruby=rose-red or pink spinel. 

 Barite=barium sulphate. 

 Basanite=velvet black, flinty quartz. 

 Bastite=variety of bronzite. 



Beckite=silicified coral shells or fossiliferous limestone replaced by silica. 

 B eekite = b eckite . 



Bemiscite=salmon-colored feldspar from Bemis, Maine. 

 Benitoite=blue barium and titanium silicate. 



Beryl=aluminum and beryllium silicate with small amounts of other elements. 

 Beryllonite=beryllium and sodium phosphate. 

 Bishop's stone=amethyst. 



Bixbite=red and rose-colored beryl from Utah. 

 Black amber=jet. 

 Black lava glass=obsidian. 



Black opal=opal in a dark matrix; also opal with vivid colors. 

 Blood agate = flesh-red, pink, or salmon-colored agate from Utah. 

 Blood jasper=bloodstone. 

 Bloodstone=massive dark-green jasper (plasma) with red or blood-colored spots; also 



hematite (German usage). 

 Blue chrysoprase= chalcedony stained blue with chrysocolla. 

 Blue john= dark-blue fluorite, tinged with violet. 

 Blue malachite = azurite. 



Blue moonstone=blue chalcedony from the Death Valley region, California. 

 Blue rock=lapis lazuli from California. 

 Blue white=diamond of highest grade. 

 Bobrowska garnet=grossularite (garnet). 

 Bohemian diamond=rock crystal (quartz). 

 Bohemian garnet=dark blood-red pyrope (garnet). 

 Bohemian topaz=yellow quartz. 

 Bohemian ruby=red or rose quartz. 



