Posting photos of pet wood specimens for new member.

looks like nevada wood to me !value may be .50 a pound

Thanks Roy. Probably best left as yard rocks.

mac, we look for rich colors and sharp patterns. LOTS of wood out there that does not meet those credentials.

It is hard to find such. No problem, your pieces are fine landscape specimens. I would treasure them in my yard.

Those are cool. Wonder if the hole bored into #2 was pre-petrification?

Really outstanding specimens though, they would look great in any collection.

Peace,

Rich

Some complicated chemical formulas in minerals related to Carnotite Mr Rick:

"Related mineral species[edit]
Several related mineral species exist, including: margaritasite ((Cs,K,H3O)2(UO2)(VO4)2·H2O) and tyuyamunite, (Ca(UO2)2(VO4)2·5-8H2O)."

Formulas like that are things of nightmares for a chemistry student.
The earth generates some insane chemicals. Radiation ads another twist.



I know you work with gems. Check out tourmaline. One of the most complicated chemical formulations:


The Chemical Formula of Tourmaline
Tourmaline is not a single mineral, but a group of isomorphous minerals with an identical crystal lattice. Each member of the Tourmaline group has its own chemical formula, due to small differences in their elemental distribution. The formula of the Tourmaline group is very complex, since it contains many elements and many combinations of elements. It is one of the most complicated chemical formula of all minerals.

A simple generic formula for the Tourmaline group is:
X1Y3Al6(BO3)3Si6O18(OH)4
Where:
X = Na and/or Ca
Y = Mg, Li, Al, and/or Fe2+

This creates the formula:
(Na,Ca)(Mg,Li,Al,Fe2+)3Al6(BO3)3Si6O18(OH)4

In some less common varieties, the Al may be replaced by other elements. For example, in Uvite, the Al is partially replaced by Mg.

This expands the formula to:
(Na,Ca)(Mg,Li,Al,Fe2+)3(Al,Mg,Cr)6(BO3)3Si6O18(OH)4

The rare member Buergerite contains three O atoms and one F atom in place of the OH radical. A Buergerite molecule also contains an Fe atom that is in a 3+ oxidation state.

This further expands the formula to:
(Na,Ca)(Mg,Li,Al,Fe2+,Fe3+)3(Al,Mg,Cr)6(BO3)3Si6O18(OH,O,F)4

The chemical formula for Tourmaline can be written several different ways.
Note that there are several additional forms of Tourmaline that further alter the formula. These forms are extremely rare and not applicable for this guide.

The chemical formula of individual members of the Tourmaline group are:
Schorl:
NaFe2+3Al6(BO3)3Si6O18(OH)4
Dravite:
NaMg3Al6(BO3)3Si6O18(OH)4
Elbaite:
Na(Li,Al)3Al6(BO3)3Si6O18(OH)4
Liddicoatite:
Ca(Li,Al)3Al6(BO3)3Si6O18(OH)4
Uvite:
Ca(Mg,Fe2+)3Al5Mg(BO3)3Si6O18(OH)4
(Note that the one Al atom is replaced by a Mg atom)
Buergerite:
NaFe2+3Al6(BO3)3Si6O18O3F
(Note that the OH radical is replaced by three O atoms and one F atom. This leaves a space open for one more positive charge, which is compensated by three Fe3+ atoms (as opposed to Fe with a 2+ charge).


Got a headache ?

jamesp,
You have to be my favorite person ever!!! Even though yes you do make my brain hurt! I HAVE TO ASK (told you I was THAT student), are you a retired chemist/geologist/physicist ?

jamesp , there are several very interesting isomorphous gem mineral species. That's what makes them hellish for average folks to really understand. Garnets are one. There's probably no such thing as a "pure" garnet species because of the property of miscibility -- they merge with one another in given series. They're actually a mineral group, with each species having its own distinctive chemistry playing varying themes on that basic chemical structure with many, many grace notes.

For that reason, like tourmalines, they represent some of the widest color variations of all minerals. Ditto corundum, feldspar and several others. In fact if you're in a masochistic mood, try working out the chemical variations in feldspar. That's a guaranteed headache-maker.

I remember a session had with you and garnets. Every color, except one color(blue ?) is extremely rare.
Taking the word of the experts that these minerals are complicated.

jamesp : Not sure if I'm reading your comment accurately, but there are blue garnets. They're color-changers only from Madagascar (so far known) and one of their hue positions is blue. They'e rare and expensive, as are some of the other color-change garnets like those with alexandrite-like CC (red to green). So the old saying "Every color but blue" is now obsolete. They were discovered just a few years back and no one knows what other new garnets may be found, especially in the "garnet factory" of East Africa in the Great Rift region.

Some of the most intriguing (to me) are the rare "rainbow" garnets with opal-like iridescence. They're mainly found in Japan, Mexico and one U.S. location to date. If you want to do some garnet study, here's a fairly straightforward guide: gemologyproject.com/wiki/index.php?title=Garnet