quartz layer

I think these are caused by cracks in the rocks (the grey rock) which then fills with different material and then crystallization occurs. But I'm not entirely certain. Farmerman will know for sure.

As for why some crystal formations seem to be bifurcated lengthwise, I'm not sure, but I would guess it has to do with the crystals growing from two opposing surfaces and then eventually meeting in the middle, but not quite matching up.

good macro shots. I scrolled through your whole slide show. DID you shoot that spier through an ultraviolet light" or did you mess with the color post processing?

Your ntive rock is a gneiss that hs been faulted slightly cause you can see "drag folding" on each side of the qtz vein. The qtz vein is intruded into the fracture while its moving and its made a beautiful emplacement. I wish you could get another shot with a peso in the field of view. Just remember to always have something in your photos so we can judge the sizes of things.

Its a real beauty of a qtz vein. The rusty nature (ferruginous quartz) makes me think it could be metal bearing like pyrite or gold. Is this an areaw here gold was found in the past? I recall where you mentioned where you were from and where some of the shots were made.
The second shot looks like qtz OR even selnite (I cant tell from a pic. If you take some sample , if it can dissolve in water, its selenite ( gypsum). If its qtz its in a thing we call a VUG, which is like a geode except it forms from hot gases and liquids containing a silica solution which deposits usually on the walls of moving fractures or folding rocks.


PS, Im a hobbyist in photog. What kind of macro do you use?

Thank you guys.
I didn't take the photos of the slideshow, I not even reach hobbyist level in photography, that place is Palo Duro Canyon in Texas, the guy that took them would be flattered. Farmerman, I bet you have great stuff, do you have a flickr account or other where we can see some shots? My stuff is from Tijuana, semiarid region.
http://www.flickr.com/photos/51986587@N04/sets/72157634573360366/
Indeed, there was a gold rush between 1800 to 1900, rumors of gold findings were spread, accurately or not, crews from the US crossed on hearing of these rumors. But, due to the scarcity of water people obtained not great quantities of gold, mainly by panning. Then they realized that it was more profitable to rise livestock or to dedicate to other activities. I have seen several fragments of ferruginous quartz hither and thither.
I put my keys as size reference when possible, I think the quartz has pirite. Standing on a nearby hill I noticed some granite rocks have a layer of quartz, I suppose the fracture occurred when these rocks were part of the bedrock. At some point the layer makes a zigzag, how can it be? In the site I found this conspicuous rounded rock intruded into the bedrock: http://www.flickr.com/photos/51986587@N04/9252174200/sizes/l/in/set-72157634573360366/ I suppose it is rounded because it was exposed to weathering but how it became intruded and buried into the bedrock, I am not quite sure.

Indeed, it looks like two opposing sublayers.