CO
COALINGITE
COBALT-PENTLANDITE
COBALT-ZIPPEITE
COBALTAUSTINITE
COBALTITE
COBALTOKORITNIGITE
COBALTOMENITE
COCCINITE (?)
COCHROMITE
COCONINOITE
COERULEOLACTITE
COESITE
COFFINITE
COHENITE
COLEMANITE
, with photos
COLLINSITE
COLORADOITE
COLQUIRIITE
COLUSITE
COMANCHEITE
COMBEITE
COMBLAINITE
COMPREIGNACITE
CONGOLITE
CONICHALCITE
CONNELLITE
COOKEITE
COOMBSITE
COOPERITE
COPIAPITE
COQUANDITE
COQUIMBITE
CORDEROITE
CORDIERITE
CORDYLITE-(Ce)
CORINDON
, with photos
CORKITE
CORNETITE
CORNUBITE
CORNWALLITE
CORONADITE
CORRENSITE
CORVUSITE (?)
COSALITE
COSTIBITE
COTUNNITE
COULSONITE
COUSINITE
COVELLITE
, with photos
COWLESITE
COYOTEITE