Lapidaryforum.net

Let's Rock => Rock Talk => Topic started by: Grayco on February 24, 2017, 07:18:26 PM

Title: Red tigers eye?
Post by: Grayco on February 24, 2017, 07:18:26 PM
I went to a fellows house today to buy some plexiglass.  While I was there I told him I'm a rock hound.  He sold me a small box of rocks.  A few cut thundereggs a few chipped up crystals and a few interesting other stones.  But then I found a 2" long 1-1/4" square red tiger's eye.
I had never heard of it before.  Here's a few pictures.
Title: Re: Red tigers eye?
Post by: Orrum on February 24, 2017, 07:20:37 PM
Probably heat treated.
Title: Re: Red tigers eye?
Post by: Grayco on February 24, 2017, 08:44:44 PM
Does Tiger's Eye ever occur red "naturally"?

Is there any problems that occur when Tiger's Eye is heat treated (or any other rock for that matter)?
Title: Re: Red tigers eye?
Post by: southerly on February 24, 2017, 09:02:20 PM
No problem with it being heat treated. Legend has it that is does occur naturally, most is created by heating golden tiger eye. The most problematic is the blue tigger eye (hawkes eye) as the asbestos fibres are less silicated.

Nice chunk, it was a popular lapidary material once upon a time, now out of fashion, but still cuts lovely cabs.

David
Title: Re: Red tigers eye?
Post by: Orrum on February 25, 2017, 05:40:51 AM
Natural heat treatment by lightning strike maybe? I read somewhere that the original beautiful color Tanzania was found by a shepherd on n a hillside after lightning strikes to the area. who knows God made em n all right?
Title: Re: Red tigers eye?
Post by: vitzitziltecpatl on February 25, 2017, 06:59:12 AM
Have read somewhere natural red might be possible if near the surface during a wildfire. Searching for variegated tiger eye should yield images of rough with red mixed with gold and blue.

The more uniform red is a good clue the piece was subjected to uniform heating, as in your oven at home. Saw times and temps somewhere once for do-it-yourself red.
Title: Re: Red tigers eye?
Post by: lithicbeads on February 25, 2017, 10:12:58 AM
In the American west natural coal fires cook rocks on a regular basis. Cooking golden tigereye red was a standard thing 40 years ago but you need an oven that goes to 800 degrees F.
Title: Re: Red tigers eye?
Post by: gemfeller on February 25, 2017, 10:49:05 AM
In the American west natural coal fires cook rocks on a regular basis. Cooking golden tigereye red was a standard thing 40 years ago but you need an oven that goes to 800 degrees F.
Not disputing you, perhaps you're referring to commercial processes. But I did it successfully years ago in a standard kitchen oven at far less than 800 degrees.  Don't recall the actual heat settings but I buried the slabs in sand to avoid sudden temperature shock and brought the temps up and down slowly with a several-hour-long heat soak. I let the oven cool overnight before opening the door. 

I recall seeing large pieces of unheated variegated tiger's-eye that combined yellow, green and red but the red was more a light strawberry color, not the even dark-toned reddish-brown in the images shown here.   
Title: Re: Red tigers eye?
Post by: finegemdesigns on February 25, 2017, 11:54:54 AM
In the American west natural coal fires cook rocks on a regular basis. Cooking golden tigereye red was a standard thing 40 years ago but you need an oven that goes to 800 degrees F.
Not disputing you, perhaps you're referring to commercial processes. But I did it successfully years ago in a standard kitchen oven at far less than 800 degrees.  Don't recall the actual heat settings but I buried the slabs in sand to avoid sudden temperature shock and brought the temps up and down slowly with a several-hour-long heat soak. I let the oven cool overnight before opening the door. 

I recall seeing large pieces of unheated variegated tiger's-eye that combined yellow, green and red but the red was more a light strawberry color, not the even dark-toned reddish-brown in the images shown here.

I think I read somewhere that you can do it at 500°F.
Also the red color is considered to be stable and there are types showing up now on eBay with hematite. The hematite areas are surprisingly strong also which I didn't expect.

(http://www.zbestvalue.com/images24/25-redtigereye-hematite.jpg)

Title: Re: Red tigers eye?
Post by: olgguy on February 25, 2017, 01:54:07 PM
That's a nice chunk. I had some a few years ago with the Hematite lines. The cab is 73 x 15.9 x 5.3 mm.
Title: Re: Red tigers eye?
Post by: finegemdesigns on February 25, 2017, 05:23:39 PM
Nice. The material is hard enough you can do sharp points.
Title: Re: Red tigers eye?
Post by: Grayco on February 25, 2017, 06:26:29 PM
That's a nice chunk. I had some a few years ago with the Hematite lines. The cab is 73 x 15.9 x 5.3 mm.

That really looks like my piece.  The black in mine is really dark.  There is about 1/8" crust on the top and bottom.  What does it look like on the top of the grain?
Title: Re: Red tigers eye?
Post by: Grayco on February 25, 2017, 06:29:33 PM
Nice. The material is hard enough you can do sharp points.

That's a nice cab.  I'm looking forward to doing something with this piece.  I' not sure what it will be yet but it is a usable size.
Title: Re: Red tigers eye?
Post by: vitzitziltecpatl on February 25, 2017, 07:51:49 PM
I've never tried heat treating tiger eye. Here's a link to another board where some folks tried different methods - with varying degrees of success.

http://andy321.proboards.com/thread/47540?page=1

Here's a link to where I probably saw the "home baked" method described.

http://minerals-n-more.com/tiger_eye_info.html

If anyone on this board tries it, please post your results.
Title: Re: Red tigers eye?
Post by: ToTheSummit on February 26, 2017, 08:34:23 AM
I have some tiger eye here, some with the hematite in it.  I also have a small kiln given to me by my uncle (who is a potter).  I've long thought about heat treating some stones just to see what happens.  Maybe tiger eye is a good place to start.

Heres an example of the yellow tiger eye with hematite that I have (I also have blue and wonder how that would react to heat?)
(http://img.photobucket.com/albums/v521/ToTheSummit/Random%20Rocks/TigerEyeCab_zpsihapidcf.jpg) (http://smg.photobucket.com/user/ToTheSummit/media/Random%20Rocks/TigerEyeCab_zpsihapidcf.jpg.html)
Title: Re: Red tigers eye?
Post by: olgguy on February 26, 2017, 11:01:13 AM
I like the natural blue the way it comes. This one is 42.7 x 30.5 x 7.5mm
Title: Re: Red tigers eye?
Post by: peruano on February 26, 2017, 01:17:26 PM
Olgguy took the words out of my mouth as I was pondering a post.  I bought a couple of small pieces of the Blue Tigereye as grab a handful tumbles at the Kemberly Diamond Mine in South Africa.  When I got home to the USA, I kicked myself for not spending more time and spending a bit more for greatly distinct rocks from S. Africa.  The kimberlite pieces that they gave away at the mine tour, yielded no diamonds for me. 
Title: Re: Red tigers eye?
Post by: olgguy on February 26, 2017, 01:50:52 PM
As with all good rock, if you don't see a lot around, when you find it, BUY.
Title: Re: Red tigers eye?
Post by: Grayco on February 27, 2017, 05:30:59 AM
Very Cool Cab! :headbang: That's a great piece!
Title: Re: Red tigers eye?
Post by: Orrum on February 27, 2017, 05:52:56 AM
Cabtastic olhuy!!!
Title: Re: Red tigers eye?
Post by: Grayco on February 28, 2017, 05:31:07 AM
I have some tiger eye here, some with the hematite in it.  I also have a small kiln given to me by my uncle (who is a potter).  I've long thought about heat treating some stones just to see what happens.  Maybe tiger eye is a good place to start.

Heres an example of the yellow tiger eye with hematite that I have (I also have blue and wonder how that would react to heat?)
(http://img.photobucket.com/albums/v521/ToTheSummit/Random%20Rocks/TigerEyeCab_zpsihapidcf.jpg) (http://smg.photobucket.com/user/ToTheSummit/media/Random%20Rocks/TigerEyeCab_zpsihapidcf.jpg.html)
This is an awesome cab.  There is so much going on in it!  The hematite really adds to it!
Title: Re: Red tigers eye?
Post by: Steve Ramsdell on March 08, 2017, 07:34:20 PM
Red tiger eye is heat treated.  Most tiger eye is associated with iron deposits.  I've heard the iron is what reacts to the heat.  The blue bands keep their appearance.  The treated stone works just like the untreated.  If I remember they don't really heat the tiger eye much.
Title: Re: Red tigers eye?
Post by: David Myers on April 03, 2017, 01:18:21 AM
Don't cook this one . . . it's too awesome already!  ;-)