154 



Beryl. 



Colemanite. 



Danburite. 



Datolite. 



Case di 



Corundum. 



Spinel. 



Silicate of alumina and berylla (see emerald, page 19, and 

 gem-cases 78, 49). 



7929, Gulf Stream Tin Mine, New England. 



5416, "Wicklow, Ireland ; in granite ; also in case 120, from 

 tlie same locality, associated with sclaorl. 



7422, Maine ; good crystals.* 



Uorate of lime (hydrous) ; California. 



Borate and silicate of lime ; IS'ew York State. 



Borate and silicate of lime (hydrous) ; Colebrook, Tasmania. 



Oxides. Oxide of aluminium (see sapphire and ruby, page 

 17, and gem-cases 78, 49 ; also emery, page 131, case 91). 



6992, E-ussia : in matrix. Berrima. Victoria (variety barJc- 

 li/ife) . 



GaJinife, oxide of zinc, aluminium, magnesium. 



8545, Sandy Creek, Tenterfield ; colourless masses consisting 

 of microscopic octahedral crystals. 9187, Broken Hill, with 

 galena. 



Pleonaste, oxide of magnesium, iron and aluminium. This is a 

 black spinel, frequently found in gem sands ; in octahedral 

 crystals when not too much water-worn. Wingecarribee Siver 

 (Berrima), Brindabella. 



Case 99. 



Epsomite. 



Anhydrite. 

 Gypsum. 



GROUP V. 



Sulphates. 



Hydrated sulphate of magnesia ; a secondary mineral, with a 

 beautiful acicular structure. 



Sulphate of lime ; a blue variety from Bleiberg, Carinthia. 



SeJenite, hydrated sulphate of lime ; the well-known mineral 

 used in the preparation of plaster of Paris (see page 129, 

 case 106). Characterised by its softness, being easily scratched 

 Avith the thumb nail. It may occur earthy, massive, or crystalline. 



• Crystals of enormous size have been found in some American localities. 



