184 BULLETIN 118, UNITED STATES NATIONAL MUSEUM. 



Chesterlite=microcline feldspar from Chester County, Pennsylvania. 



Chiastolite= variety of andalusite with crosslike marking. 



Chinarump= petrified wood from Arizona. 



Chlorastrolite= impure variety of prehnite or thomsonite. 



Chloromelanite=dark-green to nearly black jadeite. 



Chloropal=green opal from Silesia, Germany. Mineralogically, a hydrous iron silicate. 



Chlorophane= variety of fluorite which phosphoresces with a greenish light on being 



slightly heated as by friction or by the heat of the hand. 

 Chlorospinel=green spinel. 

 Chlorutahlite=utahlite (compact variscite). 

 Chondrodite= silicate of magnesium and iron, with fluorine. 

 Chrome garnet=uvarovite (garnet). 

 Chromic iron=chromite. 

 Chromite= chromium and iron oxide. 

 Chrysoberyl= aluminum and beryllium oxide. 



Chrysoberyllus=greenish-yellow, honey-yellow, or wine-yellow beryl. 

 Chrysocarmen=very similar to carmazul. 

 Chrysocolla=green to blue hydrous copper silicate. 

 Chrysolithus=pale yellowish-green beryl. 

 Chrysolite=olivine or peridot; also light-golden chrysoberyl (incorrect usage); also 



improperly applied to any light greenish-yellow to yellowish-green transparent gem. 

 Chrysoprase= apple-green, olive-green, or whitish-green, translucent chalcedony. 

 Cinnamon stone =essonite (garnet). 

 Citrine=golden-yellow quartz. 

 Cloudy chalcedony = chalcedony with dark cloudy spots in a light-gray transparent 



base. 

 Cobaltite= metallic cobalt and iron sulphide and arsenide. 

 Cobra stone=chlorophane. 

 Colophonite==brownish-black andradite (garnet), characterized by a resinous luster; 



iron and calcium silicate. 

 Colorado ruby=pyrope (garnet). Same as Arizona ruby. 

 Colorado topaz = topaz from Colorado; also citrine (yellow quartz). 

 Common opal = translucent, only slightly colored opal without fire or play of colors. 

 Comptonite= thomsonite. 



Congo emerald ==dioptase from the Congo, Africa. 

 Copper emerald=dioptase. 

 Copper-ore gem=mixture of various copper minerals, such as green malachite, green 



or blue chrysocolla, blue azurite, red cuprite. 

 Copper-pitch ore=compact black or dark-brown mixture of iron and copper oxides. 

 Coral=hard calcareous structure secreted in or by the tissues of various marine zoo- 

 phytes. When fossilized, the calcareous matter is often replaced by silica (see 



beckite). 

 Coral agate=beckite (see coral). 



Cordierite=aluminum, iron, and magnesium hydrous silicate. 

 Cornish diamond = quartz crystal from Cornwall, England. 

 Corundum=aluminum oxide. 

 Corundum cat's-eye=corundum with a bluish, reddish, or yellowish reflection of 



light of a lighter shade than the stone itself. 

 Co tterite= quartz having a metallic pearly luster. 

 Creoline=purplish epidotized trap rock from Massachusetts. 

 Creolite=banded jasper from Shasta County, California. 

 Crimson night stone=purple fluorite from Idaho. 

 C rispi te = sageni te. 



