Last week, we went out near Pelican Point on the west side of Utah Lake to do some rockhounding. You can find Limonite after Pyrite Pseudomorph and Root Beer and White Calcite Onyx.
Limonite after Pyrite Pseudomorph
This mineral is really interesting, apparently it used to be Pyrite, then overtime the minerals around it reacted with it and turned it into Limonite, but kept the same shape. Here are some pieces I found by digging with a pick. Just make sure you sort through the clay with your hands and look for sharp corners. It's also pretty heavy it's mostly iron.
The crystals are cubic, but sometimes overlap. You can find small pieces on the surface as well where the rain erodes the surface.
Here is the spot on a map:
Onyx is all over the Mountainside in this area, just look for white rocks, when you get close you'll notice the layers.
It's supposed to look great with a smooth edge, but I don't have a rock cutter so I'll have to find one and post a picture of a cut one.
Here's a general area of where to look, but it's all over the mountainsides.
It was fun just make sure you bring shade if you go in July!