Garnet?

[tdmiller]

Question on a different rock. This photo is from a website that labels it as garnet. It is a good quality picture that shows better what my home photos don''t pick up. Anyways, I have a large white rock about 5.0 x 3.0 x 3.5" in size. There are a total of 7 or 8 stones in it. Two are large, 1" and 3/4". The others are tiny, about 1/8". Any thoughts on this, or does it join the fluorite in the ''cool rock'' collection on the mantel. My pictures are to follow.

Thanks.

 

[tdmiller]

This is a picture of mine.

 

[tdmiller]

Another view.

 

[tdmiller]

Another view again.

 

[tdmiller]

Arrows pointing to the 3/4" on the left and 1" on the right.

 

[Richard M.]

Yes, you have some classic garnet crystals which form in the cubic system just like fluorite (cubic crystals have three axes of equal length at right angles to each other). Many crystal "habits" are possible within that symmetry. Garnet crystals are usually rounded with 12 rhombic or 24 trapezoidal faces or combinations of those.

The garnet group is one of the most complicated in all of mineralogy. Based on color and lots of personal experience with garnets I''d say you probably have a member of the almandine species. It''s obvious from the images that your specimens probably have little potential as gems: almandines are very dark in tone and when faceted appear almost black in reflected light, even though light transmitted through them may be a beautiful red color. When intermixed with other garnet species like pyrope or spessartine, varieties light enough in tone to be "gemmy" can occur. Some almandines exhibit stars but they come from only a couple of places in the world.

My suggestion would be to clear a little more space on that mantel for a very attractive mineral specimen.

Richard M.

 

[Richard Sherwood]

Damn, there''s not much moss growing on you, Richard M.

My congratulations on a couple good "sight IDs".

 

[bullitmeister]

Richard, I''m new and didn''t know how to post just to you. Sorry if I''ve went about it in the wrong way.

I read your posts about "Visual Optics," and have not been able to find the book. Believe me, I''ve tried every avenue possible to find one but no luck. I''m still waiting to hear from Alan Hodgkinson, but after a month and a half, I don''t think I will.

Do you know anyone who has a copy of this book and might be willing to sell it?

Bullitmeister

 

[C Smith]

That looks just like the garnet in matrix that is so common in western North Carolina. Where did it originate?

 

[WinkHPD]

Date: 9/28/2006 4:12:46 PM
Author: bullitmeister
Richard, I''m new and didn''t know how to post just to you. Sorry if I''ve went about it in the wrong way.


I read your posts about ''Visual Optics,'' and have not been able to find the book. Believe me, I''ve tried every avenue possible to find one but no luck. I''m still waiting to hear from Alan Hodgkinson, but after a month and a half, I don''t think I will.


Do you know anyone who has a copy of this book and might be willing to sell it?


Bullitmeister

It is a great book. You might be able to get a copy from Gemworld publishing, that is where I got mine many years ago. If you call me on Monday I will give you their number, I am at home this weekend and do not have the information here.

Wink