PETA hasn't been rockhounding seriously for too long. She wrote to tell me that the Flint Ridge Chert shown below was, "my very first official rock hound". Not bad. Not bad at all. The polish is as good as I've seen.
Here in the West, we would call a rock like this, "banded jasper". Peta wrote that it's also called "flint" back in her neck of the woods. This isn't a rock from my dad's collection. Peta found this one herself!
I called this "Golden Swirl Agate" when I first started listing it for sale. I thought I could remember my dad using that name. Then I noticed a few of the "swirl" markings in broken surfaces of the rock and it became clear to me that these were crinoid stems. Not everyone agrees with me on that. If you have a different identification, let me know.
Pigeon Blood is one of the most popular agates found in Utah -- partly because it's found over a wide area. And also because it is, it comes in a wide variety of "types". I wrote an article about that here ...
Utah Red Horn Coral is, as far as I can tell, a unique fossil. Rugosa coral fossils are actually not that rare. They were a dominant life form for millions of years. A deposit can be found about a hundred miles away in a canyon near Logan, Utah. But those are small and black. It's difficult to tell that they actually are coral fossils.
But not Utah Red Horn Coral. These are some of the most beautiful fossils found anywhere. My dad was one of the first rockhounds into the only place where they're found. See my essay: Utah Red Horn Coral