CHRYSOCOLLA QUARTZ FROM THE BACAN ARCHIPELAGO, SOUTH HALMAHERA REGENCY, NORTH MALUKU PROVINCE, INDONESIA

PROCEEDINGS PIT IAGI RIAU 2006
The 35^th IAGI Annual Convention and Exhibition
Pekanbaru – Riau, 21 – 22 November 2006

CHRYSOCOLLA QUARTZ FROM THE BACAN ARCHIPELAGO, SOUTH HALMAHERA REGENCY, NORTH MALUKU PROVINCE, INDONESIA

H. Sujatmiko¹
H.C. Einfalt²

¹Jalan Pajajaran 128, Bandung 40173, Indonesia. Email: miko@melsa.net.id
²Friedenstr. 46, D 75015 Bretten, Fed. Rep. of Germany. Email: hcv.einfalt@gmx.de

ABSTRACT

Chrysocolla quartz from South Halmahera occurs in a series of basaltic pillow lavas as veins and small pods. The chrysocolla quartz is cut as cabochons which range in colour from sky blue to bluish green, uniform or mottled in appearance due to the proportion of chrysocolla and the intergrowth pattern with quartz and chalcedony. Apart from common opaque spots of native copper and cuprite and very little malachite, additional coloured minerals are present in the bluish green variety. Chrysocolla in this material seems to be largely non-crystalline. A brief account is given of the geology, gemstone deposits, gemmological characteristics, and thin section observation . Some genetic aspects of the mineralisation are discussed.