Help identifying a mineral

[Ninjafossils]

I found this gem in central Wyoming. Any idea what mineral/gem it is?

 

[Jim in Idaho]

Looks like a chalcedony quartz nodule. Nice find!
Jim

 

[tamrock]

I think Jim's right. My first thought was a gypsum crystal, but I see a matrix of non crystal forming chalcedony with in it. It's a really interesting specimen and a nice find.

 

[IAMZIM]

It's nice, you should take a pic in the sun, this pic is very dark.