Naked Science Forum

Non Life Sciences => Geology, Palaeontology & Archaeology => Topic started by: maruti.int on 04/06/2009 03:59:21

Title: How to change colour of Milk Quartz
Post by: maruti.int on 04/06/2009 03:59:21

Dear All
           How are you, I have a unique problem for you guys. I have attached a image of Sand stone tile, This sand stone is having base colour of yellow. and there are Red and White Veins in between. These white veins are made of Milk Quartz. We want to change the colour of these white veins into red. Please tell us the way to do it.
regards
varun agarwal
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Title: How to change colour of Milk Quartz
Post by: Don_1 on 04/06/2009 08:07:47

I'm no geologist, but I would not think it possible to change the colour of particular strands within a solid piece of rock of any description.

The only way I can see of achieving your goal would be if the rock you wish to colourise were porous enough to soak up a vegetable or chemical die, but then you have a problem with seepage into the surrounding rock if that too were as, or more, porous than the one you wish to colour. I'm pretty sure that sandstone is far and away more porous than any quartz.

Even if you could tint the quartz with a die, it would be subject to fading and discolourisation over time by chemical breakdown due to exposure to light, air and water. In the case of water, this could also draw the die out.

Natural quartz is coloured by impurities such as titanium and iron, while milky quartz is the result of gas and/or liquid trapped during the formation. I would doubt you can introduce these impurities once the quartz has formed.

Quartz can be heat treated to intensify and change the colour, but any heat treatment would have an effect on the sandstone in which it is trapped, and I'm not sure milky quartz would actually change colour even if you could heat treat this rock. Temperatures of 300^o C and above are required.

Take a look at this http://www.donsmaps.com/heatflint.html (http://www.donsmaps.com/heatflint.html)

Title: How to change colour of Milk Quartz
Post by: Bass on 04/06/2009 19:11:25

Quartz (silica) is not very reactive.  It is very resistant to erosion, both chemical and physical, which is why most sands are mostly quartz. 
As Don_1 points out, any attempt to change the color of the quartz seams will also affect the sandstone, since it is also made of quartz.

Title: How to change colour of Milk Quartz
Post by: jysk on 07/06/2009 06:05:59

Hello,

This is just an idea - but IF the white quartz stringers had some potassium in its makeup and IF the sandstone matrix was potassium poor - then a K-spar test would change the color of the stringers exclusively. Is there a petrologist reading this who can say whether or not potassium is ever carried in silica solution?

Mike

Title: How to change colour of Milk Quartz
Post by: JimBob on 09/06/2009 19:05:33

I don't think there is much chance quartz would have potassium in it.

Title: How to change colour of Milk Quartz
Post by: Bass on 10/06/2009 02:17:49

Aluminum, yes.  Potassium, JimBob is right.