Atleast that's what I'm calling it for now.
Some geologists agree, some don't, and some just shake
their heads.
The first thing most artifact collectors, archaeologists, and
knappers say when I show them this stuff is, "They didn't
knap that!"  But I have collected a couple of 5 gallon buckets
worth of flakes and lithic debitage from the surface of the
source site in Person County, NC, and have turned in samples
to several of the different institutions that have NC lithic
collections as proof of it's prehistoric use.
It may not have been used much, but it was used some.

Here are a couple of blocks I cut from the rough.

Pics 1,2,3

As with all rocks you will find a variety within the same
species. Here are a few slabs for variety leaning against
a large piece of the rough.
Pic 4

But I have never seen a projectile point made from this
material and have only ever found one flake of the material
off the source site. I found this flake outside of Scotland
Neck in Halifax County about 80 miles east of the source.
It is sitting on a slab of some of the same material.
The slab is wet and the flake is dry for contrast.
Pic 5

One problem with getting a definite identification on this
rock is it's age, 550 million years give or take 50 million,
and the extent it has morphed or degraded into what we
now have. One identifying characteristic of Spherulitic
Rhyolites are radiating lines from the center of the spheres.
This material has none. Have they degraded away?
Another interesting trait of this material is there is no
difference in grain size anywhere in the material. Inside the
spheres is the same as outside of them. Could this be that
it has all morphed now to the same composition?
Here are a couple photomicrographs of the spheres to show
the homogenous make up of the material now.
Pics 6 & 7

I hope to add more pics of this material in the future.
Joe

Wow! I love that big cube! Very interesting material too.

Are those circles from air bubbles or drops cooling in mud (volcanic flow, etc.) or are they organic? Trapped organisms? I would love to see this stuff compared to the rhyolite from other areas.

I ask because there is a weird material over here that seems like quartzite, but different, and within this material are some fossils. Oh never mind, pictures will speak for themselves. I swear I am going to post my finds of what I believe to be Knox chert and I will include this stuff too. I promise the pics/post are coming soon, Joe. Here is one pic of the knox chert (or what I believe to be), though.

I am pretty sure they are the same material. I will start another thread on it when I get around to that, because now I think that is not actually Knox chert, but definitely a used material.

I would love to see what a slice of the spherulitic rhyolite looks like illuminated from behind. Thin slices of that stuff turned into a luminary or a cover for a pendant light. This way you get to have the rocks all around you in your house - functional art. They get to live and not be quarantined to display only. I only have so much horizontal space for displays (especially since I got a kitten).

hey joe, i was reading about rocks last night and there was a mention of "rhythmic crystallization" for orbicular diorite. the end result is the same as this, orbs and circles. it didn't say what caused the rhythmic crystallization, though. but this is very curious. have you heard of this?

Joe the Orbicular Diorite location is closed but I have some from when it was open.  If you would like some, I will be glad to get some to you.  I was studying some this week. I was looking at the Monazites that are in this material.

Very interesting, Joe. AND very interesting about the monazite in orbicular diorite. I love monazite and have been collecting it here and there. I would love to see a picture of the monazite in the orbicular diorite.

From my understanding, diorite is a catch-all name. The Easter Island monoliths are made from a diorite. And what I have dug in over in NC is a diorite too. They don't even resemble each other. I can't seem to find diorite on mindat either.

Back to the rhythmic crystallization: what could cause that? extreme temperature flux? An external force seems unlikely, given the span of time needed to make a rock. Seems likely to be bubbles cooling slowly - a self-perpetuating force, an internal force. Or maybe it cooled to the rhythm of the earth, encapsulating that movement/energy in a graphic representation.  Time for more coffee...

Thanks for the link Joe. Really, I didn't want to know the difference between in- and ex-trusive, but I did need to know; and it turned out to be very interesting. I just wanted to be lazy about it and rely on you filling in the blanks for me.  Now I know all about igneous rock, but can't find my keys! Thanks Joe. 

I remember you not believing me when I found basalt over here in TN, but I really think it is. To me, it seem there were volcanoes all over the place a long, long time ago....like in the beginning? 

Splendid point!  I think you should call the material "Clouded Leopard Rhyolite".

D.