Question
Purple rock
I am wondering what kind of rock this is. no one seems to know.
It is about 2" long. Found in Mn. USA
Thanx, Dan
AnswerDan, my first thought is a form of agate but honestly, without seeing the rock to see the colors, surface form and other characteristics, I am not able to honestly identify the rock from a photo. I do appreciate the photo because it does at least suggest two options, one of which may be right on or both could be wrong. Someone from a rock shop needs to take a look.
My thoughts are first an agate, a form of chalcedony. These are often nodules or broken pieces made of microscopic quartz crystals locked together. For your information, the state gem of Minnesota is Lake Superior Agate. The internet is full of photos but most are polished stones. The surface erosion is sometimes seen on agate nodules, giving some idea at to the pattern of the stone interior. The color is also interesting and agates do show color beyond the common rock tones. You might want to wet the rock and see if any patterns of concentric banding show through even slightly. Depending on the surface material, banding may show in agates when unpolished.
Another possibility is a concretion. Rather than try to explain that one, here is a website telling about the rock formations called concretions:
http://en.wikipedia.org/wiki/Concretion
Best wishes in getting a firm id on the stone. If an agate, perhaps someone from a local rock and gem club would polish part of the rock for you if you want to do that.
God Bless and Peace. Thomas.
