Calcite on Aragonite, Iron Princess Quarry, Iron Knob, SA
Size 9cm x 7cm
A decent sized speciman of this unusual combination. While this mine was renowned for its specimans of calcite and aragonite crystals, specimens with both species on them were much more uncommon. One variation of these specimens is like this one where a almost pure block of massive aragonite has a caviuty in it, in this cavity grew slender needles of aragonite, and after that calcite crystals grew over the aragonite crystals completely covering them. The last two photos show the back of the speciman which is massive aragonite enclosing a lone lump of hematite ore.
Unusual speciman and not many recovered. Mine is mined out, closed and backfilled.