Arizona outcrop ID help please

ShadowsAz · Oct 25, 2009

While cutting across an area in Arizona, (on my way to prospect for gold) I found this
outcrop. I have never come across anything like it, and wondered if anyone could help with
an ID or even with where I might research something like it. I have enclosed three photos
of the "sort of egg or round shapes" as well as three photos of the "vein". These are both
in the same outcrop. Thanks for looking!

Pirate Dirty Jack Rackham · Oct 27, 2009

I cant tell you anything about what you found but I can tell you that Arizona has some of the most interesting and unique geology in the southwest, hell probably the whole U.S.!

ShadowsAz · Oct 27, 2009

" Unique geology " fantastic views, interesting people, and Gold, silver, copper, gemstones!
I could do commercials for the Travel Channel .... LOL .... I did however have someone suggest
that the outcrop looked like "nodules in rhyolite" (SP ?) and that I might look into some research
on Opal. So that is my new field of study, as I begin, all I know is Opal is my wife's birthstone...
I obviously have a long way to go.......

Weddle546 · Oct 28, 2009

Im new to the site and i am an Arizona rock hound, The vein could possibly be tigers eye? hard to tell from the picture, but if not is probably an agate. the nodules happen quite often, they are deposits that boiled up thru ancient mud i believe. They are probably quartz and look pretty cool if you cut and polish them. Keep a lookout for those blues! (im a gem silica nut). Really cool out cropping you found there. looks like the area may be rich in minerals.

Weddle546 · Nov 1, 2009

OH YEAH! so you have the blue fever too? lol. i grew up with my uncle always hunting it. Always some story somewhere leading us to an old mine. He usually has atleast 10 pounds of the best grade laying around.

mrs.oroblanco · Nov 22, 2009

Cannot really tell from your pictures (sorry), but, maybe thunder eggs.

Do any look like these?

DanB · Nov 25, 2009

Looks like some basalt and chalcedony.....(Chalcedony has a waxy luster, and may be semi-transparent or translucent. It can assume a wide range of colors, but those most commonly seen are white to gray, grayish-blue or a shade of brown ranging from pale to nearly black.) Hope this helps......Agate is associated with these rocks.

hope this helps

db

mrs.oroblanco · Nov 25, 2009

There is definitely chalcedony in the pictures.

Arid-Zone-A-seeker · Jan 29, 2010

That is Gas pocket agate, very common, usually found after they have eroded from the lava.Crack some or cut some open they should have lines like a topo map, called fortification. They will probably fluoresce light green, lime green.

extractor · Jan 29, 2010

Weddle546 said:
Im new to the site and i am an Arizona rock hound, The vein could possibly be tigers eye? hard to tell from the picture, but if not is probably an agate. the nodules happen quite often, they are deposits that boiled up thru ancient mud i believe. They are probably quartz and look pretty cool if you cut and polish them. Keep a lookout for those blues! (im a gem silica nut). Really cool out cropping you found there. looks like the area may be rich in minerals.

Agree