Transcribed from "Rutley's Elements of Mineralogy", 26th Edition, ed. H. H. Read FRS:
ACTINOLITE, Remolinite
Comp: Basic chloride of copper, Cu2(OH)3Cl; copper, 59.4 per cent. Crystal System: Orthorhombic. Common Form: Prismatic, crystals not common. Colour: Bright deep green to blackish green. Streak: Apple green Lustre: Adamantine to vitreous; translucent to subtranslucent. Hardness: 3 to 3.5. Specific Gravity: 3.76
Tests: Heated in closed tube, gives off water and forms a grey sublimate; easily soluble in acids; on charcoal, fuses in time to metallic copper, colouring the flame azure-blue (chloride) and forming a brownish and greyish-white deposit on the charcoal which volatizes in the reducing flame, again giving an azure-blue colouration.
Occurrence: Occurs in the zone of weathering in some copper lodes, especially when this weathering has been effected under desert conditions; occurs at Botallack Mine, St. Just, Cornwall; Los Remolinos and the Atacama Desert, South America; and Burra Mine, South Australia.