218 DESCRIPTIONS OF MINERALS. 
Aragonite. 
Trimetric. In rhombic prisms; J A 7=116° 10’. Cleavage 
parallel with /. Usually in compound crystals having the 
form of a hexagonal prism, with uneven or striated sides ; 
or in stellated forms consisting of two or three flat crystals 
crossing one another. ‘Transverse sections of some of the 
compound crystals are shown in figs. 1 to 4. 

Occurs also in globular and coralloidal shapes; also in 
fibrous seams in different rocks, 
Color white or with light tinges of gray, yellow, green and 
violet. Lustre vitreous. ‘l'ransparent to translucent. H.= 
35-4. G.=2°93 
Composition. Same as for calcite, and its action before 
the blowpipe and with acids is the same, except that it falls 
to powder readily when heated. Some varietics contain a 
few per cent. of strontium carbonate, but this is not an 
essential ingredient. Distinguished from calcite by the 
absence of the cleavage of the latter, as well as the ecrystal- 
line form ; also by its higher specific gravity. 
Obs. Aragonite occurs mostly in gypsum beds and in 
connection with iron ores; also in basalt and other rocks. 
The coralloidal forms are found in iron ore beds, and are 
called #los ferri, flowers of tron. They look like a loosely 
intertwined or tangled white cord. | 
The flos-ferrt variety occurs at Lockport with gypsum ; 
also at Edenville, at the Parish iron ore bed in Rossie, and 
in Chester County, Pennsylvania. Aragon in Spain affords 
six-sided prisms of aragonite, associated with gypsum. ‘his 
locality gave the name to the species. Also found at Bilin, 
in Bohemia, ‘Tarnowitz in Silesia, and other places. 
