Australia is the primary source of the world’s gem Opal and if no new deposits are found soon it will become even rarer than it is now. Making it one of the rarest gemstones in the world.

Opal is highly sought after, as no two stones are ever the same. Each stone is totally unique.
Australian Opal is the product of deposits of silica from the inland sea, that used to occupy the centre of Australia millions of years ago, and heavy seasonal rains. The water from the inland sea, combined with the heavy seasonal rains soaked deep into the cracks and crevices of underground rock, carrying with it the dissolved silica.

As the inland sea dried up and the water evaporated, it left behind solid forms of silica which formed Opal within these layers of underground rock. Under special conditions this opal can aquire unrivalled brilliance with vibrant colour flashes commonly called play-of-colour. These deposits were formed millions of years ago.

Opals containing Red flashes are the most expensive, and the rarest. But opal is a very individual stone and when most people look at parcels of opal they nearly always find something with colour tonings that matches their individual taste.

Christensons, in conjunction with Australian Gem Mines, own and operate an opal mine in outback South Western Queensland. Predominately the opal mined here, is boulder opal, found in mostly ironstone deposits and also within the sandstone.