This piece of Australian Boulder opal is from the Koroit area. We didn't pick it but we did but it straight from the source through a gem auction. We have a few pieces set aside to cut and polish, and a couple of pieces like this, loose, rough opal for sale.
This is a rare occurrence for us. This opal crystal has deep blues and turquoise greens in it.  It has big patches of colour for such a seemingly small piece. It has great potential for a skilled lapidary artist. These colours are suitable for lapidary work. There is real potential for making money from this opal if you know how to cut it. We are a little nervous to approach lapidary work on opals, but we'll work up to it.
This opal crystal on boulder will make a lovely display piece in any crystal collection. 
There's a lovely legend from the Aboriginal people about how the Gods made the world. When they were done, they put all the leftover colours into the opals. It's one of our favourite crystal stories.
In terms of healing, crystals like opal are renowned for a somewhat chaotic energy. This earned them the reputation of being bad luck to wear. If you liked Moldavite, you will love opal.