This is a super cool rock that a friend grabbed out of our rock yard while visiting. He picked it up and exclaimed, "that's a hot rock!" So we took it right into the saw and these few slabs were the resulting cuts. What a hot rock indeed! It looks to be a stick agate of some kind or possibly a quartz after barite pseudomorph but I am not entirely sure. This is one of those stones you just don't see everyday.
2.6"x2.5" 0.24" thick