Fire agate - beautiful, unusual... but a tricksy little devil to try and photograph!

Love this stone!  A member of the quartz family, they have crystals of an iron mineral over the botryoidal chalcedony growth beneath (love the word botryoidal – the definition is “having the form of a bunch of grapes”). Although the stone itself is brown, the iron mineral layer produces iridescence, so the stone appears to have a coloured bubble effect inside. Not the best photo but hopefully you can see the effect…