COMPOUNDS OF CALCIUM. OTT 
gypsum in limestone. At Camillusand Manlius, N. Y., and 
in Davidson County, Tenn., are other localities. Fine crys- 
tals of the form represented in figure 5 come from Poland 
and Canfield, Ohio, and large groups of crystals from St. 
Mary’s in Maryland. ‘Troy, N. Y., also affords crystals in 
clay. In Mammoth Cave, Kentucky, alabaster occurs in 
imitation of flowers, leaves, shrubbery, and vines. Alabas- 
ter is obtained at Castelino in Italy, 35 miles from Leghorn. 
Massive gypsum occurs abundantly in New York, from 
Syracuse westward to the western extremity of Genesee 
County, accompanying the rocks which afford the brine 
springs; also in New Brunswick, especially at Hillsboro’, 
where part is excellent alabaster; in Hants, Colchester, and 
other districts in Nova Scotia; also in Ohio, Illinois, Vir- 
ginia, Tennessee, Arkansas,and Nova Scotia; and in con- 
nection with the Triassic beds of the Rocky Mountain 
region; also abundant in Nevada and California. It is 
abundant also in Europe. 
Gypsum, when calcined, loses its water, becomes white, 
is easily ground to a powder. ‘This powder, when mixed 
with a littleewater, takes up water again and becomes hard 
and compact. ‘This gypsum is plaster of Paris, and is used 
for taking casts, making models, and for giving a hard finish 
to walls. Alabaster is cut into vases and various ornaments, 
statues, etc. It owes its beauty for this purpose to its snowy 
whiteness, translucency, and fine texture. Moreover, owing 
to its softness, it can be cut or carved with common cutting 
instruments. Gypsum is ground up and used for improving 
soils. 

Anhydrite. 
Trimetric. In rectangular and rhombic prisms, cleaving 
easily in three directions, and readily breaking into square 
blocks.  JAT=100° 30'5 lé@Al¢=85° and 
95°. Occurs also fibrous and lamellar, often 
contorted ; also coarse and fine granular, 
Anhydrous Calcium Sulphate. 



and compact. 12 
Color white, or tinged with gray, red, or 2. 
blue. Lustre more or less pearly. ‘Trans- igi oe 
parent to subtranslucent. H.=3-3°5. G. ama Gf 
2-9-3, — SJ 
Composition. CaOgS=Sulphur trioxide 3. 
58°8, lime 41°2=100. It is an anhydrous ie 
; : ‘ 1 
calcium sulphate. B.B. and with acids, ae s 
