As some of you know from a former thread on the subject, I occasionally like to slither down muddy holes in the earth and explore caverns. Well, I just took a great trip and I have photos!
As I explained before, I live in what is known as the TAG caving region (Tennessee/Alabama/Georgia,) which is widely known as one of the best caving regions in the world.
I had a whole long OP already written, then the boards went down, and so now I’m giving you the abbreviated second version. I’ll post more photos later.
We went to two caves on this trip, both rather small, but each absolutle breathtaking in its own way. The first was a cave that had never been exposed to the outside world until road crews were blasting a road cut through a ridge. They opened a narrow entrance and exposed an amazing cave. It had been so isolated and so stable for so long that there was plenty of opportunity for amazingly delicate formations to grow. There are incredibly fragile, hairy calcite crystals growing everywhere, sparkling jewel-like encrustations in the rocks, and twisty, wildly improbable helictites.
One photographic caveat: on the trip described in the previous thread, I managed to completely ruin a very nice camera, despite my precautions. It ended up costing $350 to have it rebuilt. Therefore, it’s cheap, disposable cameras from now on. The pictures are not the best quality, but you should be able to get an idea…
Cave bacon - I wish I could have disabled the flash on this one, because one of my buddies was shining his headlamp on the formation from the back, and you could really see its colors and translucency. Very thin and fragile.
Cave pool - We came across this tiny, perfect little pool. Its edges are a formation called a rimstone dam, and the water is just crystalline and perfectly clear. Note the small stalagmite in the back. It appears to be floating on the surface of the pool, but is connected to the stone by a narrow strip of rock. Neat illusion from the right angle. And yes, I’m aware that the stalagmite in the foreground is aggressively, violently phallic. 
Cave turnips - Neat little helictitic formations. It looks like they’ve been planted and we’re seeing them from the underground side.
Cave mushrooms - These are mind-blowing little formations. Essentially, they started out as normal soda straws, and at some point, they stopped dripping downward and started forming a horizontal disc that expanded as more water evaporated. Really bizarre, exotic stuff. No one knows how it happened, and as far as I know from everyone I’ve talked to, this may be the only cave in the world where it happens.
Hairy column - This is a rather crappy pic, but you can see that the column is covered in hairy calcite crystals. This formation is incredibly delicate. A touch or a breath would have destroyed the crystals.
Here are a couple of cave vistas that give you an idea of what the rest of the cave looked like.
After we got out of that cave, we drove a couple of miles and dropped into another one. This one was described to me as a very small cave “which only has one formation…and that’s all it needs.” We took a group photo and dropped into a little borehole immdiately behind us under the boulder we’re sitting on.
What we found was breathtaking. There, in the dark, was a stalagmite, true enough, but it was unlike anything I had ever seen. It resembled a ziggurat, or a Mayan step-pyramid. It was perfectly symmetrical like Mount Fuji, and each of the steps, or terraces, was a shallow rimstone depression filled with crystal clear water. The whole effect was one of an elegant, artistically designed fountain. This was the stalactite feeding it water and minerals, and this is the ziggurat. You can see the water in the terraces.
I know this is a crappy photo, so here is the whole complex as photographed by another of our group, and lit by our headlamps. Absolutely astonishing formation.
Any other folks want to share?