* Actynolite. 459 ®blique rhomboidal four-fided prifm, having its acute lateral edges truncated. I he cryftals are long, often acicular, and imbedded. ■The lateral planes are fmooth, and often longitudi nally {freaked. Externally it is fplendent, internally Ihining, and 'ntermediate between vitreous and pearly. Fra&ure mod; commonly radiated, from very Iniall to pretty broad radiated, almofl: always fcopi- formly, and diverging radiated, feldom parallel; fometimes it is foliated, with an indidinct two fold cleavage. Fragments fometimes wedge fiiaped and fplin- ter y, fometimes indeterminately angular, blunt edged. It occurs in wedge-fhaped prifmatic concretions, alfo ln large, coarfe, and fmall grained didinfd concretions. 1 he maflive is intermediate between tranducent, and banfluccnt on the edges, and fometimes even verges ° n tranfparent. Crydals tranfparent. Semi-hard in a high degree. Fretty brittle. Fretty difficultly frangible. Not particularly heavy, approaching to heavy. Specific gravity, from 3,000, to 3,310. Kirwnn. Chemical Characters. ^ is fufible without addition, into a blackilh fcoria ^cording to Wiedenman, but according to Lelievrc mt0 a £iayilh black enamel- Ctnstiincnl