TinyTuesday...Mineral, Crystal

It wasn't until I'd photographed my opal ring, that I discovered opals are neither minerals or crystals
'Opal is a mineraloid because it is amorphous hydrated silica.' Whatever that means!
Nevertheless, it will have to do.
It's a very sentimental ring, given to me many years ago, and despite some stones forever falling out and being replaced, I would never part with it. It brings back memories of happy times, places, people.
I  can't believe how blue the sky is now after a very grey and wet start to the day...long may it last :)