Ideniutfying pegmatite

shaman15771 · May 28, 2015

We live on a quartz mountain. (yes, really) and I have been trying to identify pegmatite if any. I know it's very large crystals, but what else? Does anything else have to be mixed in too? Someone told me feldspar?

DDancer · May 28, 2015

Pegmatite's are usually feldspar material with some quartz, mica and a host of other minerals. The digging in pegmatite threads are a good example of what is typical for pegamatite bodies.

shaman15771 · May 28, 2015

Well, we've got the quartz, mica and feldspar. Problem is we're right in the middle of the woods and hard to get an overview of the lay of the land. Will try and get some pictures up this weekend.

wilfndgold · May 29, 2015

GOOGLE EARTH is your friend.

shaman15771 · May 29, 2015

How does it get rid of the trees?

wilfndgold · May 29, 2015

I dont think trees can grow out of pegmatite.

meMiner · Jul 19, 2015

Correct me if I am wrong, but won't trees and shrubs grow on pegmatite .... but sometimes you can see that there is a geologic change overtop by a change of vegetation? Especially interesting is a line of trees (eg beech) would be a possible fault and a circle pegmatite.

Eu_citzen · Jul 21, 2015

Trees don't grow on massive, unharmed pegmatite. It can though grow in cracks.

shaman15771 · Jul 21, 2015

We are right in the middle of the woods. We have quartz, mica, ffeldspar, some black rocks I think are manganese maybe. And a lot of color. White, blue, pink, red, yellow, green, brown, black. Sometimes all in the same rock. It's a puzzle for sure.

hvacker · Jul 21, 2015

Some have said trees grow taller around pegmatite because of the minerals. I don't know if that's a miner's myth or fact. I thought trees needed the three ingredients nitrogen, phosphorus, special K. Of course if you saw my garden you'd know I don't how to grow anything but cactus.

There are good examples on the web.

meMiner · Jul 23, 2015

Some types of trees grow especially well if there is underground water and if you can stand back, you can see the line of the underground stream. Many times this follows an ancient stream bed (great for gold) or a fault (good for almost anything). In theory, it is a great indicator of a place to look. In the field, usually more difficult to put into practice (for me anyway). It can also be an area disturbed by a land slide, tree planting, human disturbances/digging, etc.

IAMZIM · Jul 24, 2015

wilfndgold said:
I dont think trees can grow out of pegmatite.

What makes you think trees can't grow out of a pegmatite? I have pics of a pegmatite that was under a tree's root system, where after it was knocked over by the wind. I dug and found very large smokey quartz and fedlspar crystals. Check out some of my links.http://www.treasurenet.com/forums/today-s-finds/421302-starry-night-crystal-pocket.html. (sorry don't know other way to "link" it, as I am a little computer illiterate...) The pegmatites I hunt for crystals on are covered with trees, unless I don't get your meaning...