Richardson Thunderegg with an Unusual Centre of 'Wormy' Opal.

A curious stone, unlike anything I have seen before. People who know this site will be used to my sometimes bizarre and even unsavory comparisons by now - but I have to say it. this looks like nothing so much as a cheese that has been under attach by cheese maggots! Presumably sitting in a dirty caramel-coloured pool! That aint disparaging though - a very interesting stone!