Michel Jebrak, Eric Marcoux, Denise Fontaine; Hydrothermal silica-gold stalactites formed by colloidal deposition in the Cirotan epithermal deposit, Indonesia. The Canadian Mineralogist ; 34 (5): 931–938. doi:
Hydrothermal stalactites have been discovered in the deepest level of the Cirotan mine (Western Java), an adularia-sericite type of precious metal epithermal deposit of Pliocene age. These stalactites show a succession of colloidal silica and gold-rich sulfide bands. Oxygen isotope geochemistry indicates that hydrothermal fluids were of meteoric origin, similar to present rain water in the area. Quartz textures indicate early deposition by gel related to silica supersaturation, then of alternating bands related to deposition and drying, as shown by desiccation marks. Stalactite formation and the origin of alternating bands could be related to local input of magmatic gas.