Aussie GoldTM Orchid Mix is based on Diatomite, a natural rock product mined in Australia. Diatomite consists of the skeletal remains of microscopic single cell fresh water plants known as diatoms. These small plants developed an opaline siliceous shell-like armor for protection. Over the millennia the fossil shells accumulated on the beds of fresh water lakes in Australia and compacted into the lightweight porous rock known as Diatomite. Over the last few years, Diatomite has been tested by orchid nurseries and proved to be advantageous to orchid growing at all stages of the plants’ development.