This is soap...called Soaprock. This particular variety is called "banded opal" -- not to be confused for opal the stone. Follow the link for more info.
Dark Opal (Body Tone N5 to N7) 12 x 10 x 3mm 2.9 carats Auction #598757 Opal Auctions
Opal rock ring Australian opal ring Rough opal ring by HAWKHOUSE
Hey, I found this really awesome Etsy listing at https://www.etsy.com/listing/228724272/raw-opal-ring-australian-opal-ring-rough
Australian Opal Rock, Beautiful!!!!!
Raw Australian opal ring Stop by my Etsy Shop: www.etsy.com/shop/TeoldDesign
An amazing little selection of opals from around the world. DerHammerStein Auction
Amazing Virgin Valley Opal with a phantom by DanPickedMinerals
Opal: enhances cosmic consciousness while promoting psychic visions. Assists in bringing forth and expressing the "authentic self" | #perspicacityparty #magicgeodes #opal
Boulder Opal maze by @opalsdownunder ////// www.instagram.com/opalsdownunder www.mineraliety.com