WHAT IS PIPE CRYSTAL BOULDER OPAL?
Pipe Crystal Boulder Opal is a type of boulder opal that has only been found exclusively in Queensland, Australia to date. It is formed in round tubular holes in boulder sandstone rocks. Usually, the darker the sandstone, the darker the colours are in the opal.Read More
When cutting this type of opal, sandstone is usually left in the finished piece (most usually on the back). It usually does not have any ironstone present. It is commonly a well polished opal and often associated as a replacement for wood fossil opal; as they are somewhat similar.