I'm not certain whether this is simply a great image - or an impossible-to-turn-away-from doorway into a dark and fantastical alternate universe. Actually, it may be both. But in either case... it's a great photograph. Period.
Hi Miguel. I am glad that you like the image.
It's of a sliced and polished geode. Taken through a hand held magnifying glass.
I played with the focus until just the edge which was reflecting a light from above was sharp.