Lapidaryforum.net

Please login or register.

Login with username, password and session length
Advanced search  

News:

Welcome new members & old from the Lapidary/Gemstone Community Forum. Please join up. You will be approved after spam check & you must manually activate your acct with the link in your email

Congratulations to auscarver and his Rhodonite Cab!

 www.lapidaryforum.net

Another cabochon contest coming soon!

Pages: [1] 2  All   Go Down

Author Topic: Unknown... ?Agate, perhaps?  (Read 619 times)

0 Members and 1 Guest are viewing this topic.

Rosemaryr

  • Newbie
  • *
  • Offline Offline
  • Posts: 29
Unknown... ?Agate, perhaps?
« on: January 19, 2019, 01:25:41 PM »

I've been going through the stock of rough I have, that my dad left, and have pretty much got everything ID'ed.  Except for two slabs of the same material.  Green, swirly, partly translucent.  I tried the scratch test with a steel knife; it didn't seem to leave any indentation or scratch, although it did seem to leave a mark. Here are three pics: one dry, one wet, one with a backlight to show the translucency.

Any ideas?
Logged


rocks2dust

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 347
    • rocks2dust items on ebid.net
Re: Unknown... ?Agate, perhaps?
« Reply #1 on: January 19, 2019, 02:05:22 PM »

My first thought was variscite, but that should have scratched.
Logged
r2d

surplus odds and ends that I have on ebid.net
· Xtra gemstones
· Xcess fossils, minerals and rough
· Everything else

VegasJames

  • Full Member
  • ***
  • Offline Offline
  • Posts: 184
Re: Unknown... ?Agate, perhaps?
« Reply #2 on: January 19, 2019, 06:16:39 PM »

I am thinking possibly a slag glass. Looks like bubbles in the upper left of the slab.
Logged

Slabbercabber

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 346
Re: Unknown... ?Agate, perhaps?
« Reply #3 on: January 20, 2019, 06:15:54 AM »

It looks like Polar jade.  How about streak.
Logged

vitzitziltecpatl

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 642
Re: Unknown... ?Agate, perhaps?
« Reply #4 on: January 20, 2019, 07:32:28 AM »

Yeah, Polar/BC Jade looks right to me too.

Most of what little I know about jade is from this forum, so I was hoping one of you would ID it that way.

Heh, I even got confused by a slab of serpentine I posted a while back. It was really good serpentine... .

Rosemaryr

  • Newbie
  • *
  • Offline Offline
  • Posts: 29
Re: Unknown... ?Agate, perhaps?
« Reply #5 on: January 20, 2019, 12:32:35 PM »

I am thinking possibly a slag glass. Looks like bubbles in the upper left of the slab.

Bubbles were just the water I used to wet it with... no visible bubbles inside the slab itself.  ....and I thought that glass would have scratched with the steel.   

Logged

Rosemaryr

  • Newbie
  • *
  • Offline Offline
  • Posts: 29
Re: Unknown... ?Agate, perhaps?
« Reply #6 on: January 20, 2019, 12:37:27 PM »

Oooo, jade is a potential?  I haven't seen any jade images with that swirly look to them.

I do have another slab which *is* marked as jade from his collection, but that one looks nothing like these... that one is more of a standard, dark green nephrite style.  These two swirly slabs are both definitely different than that piece. 
Logged

Rosemaryr

  • Newbie
  • *
  • Offline Offline
  • Posts: 29
Re: Unknown... ?Agate, perhaps?
« Reply #7 on: January 20, 2019, 12:40:14 PM »

It looks like Polar jade.  How about streak.

?  What would I use to test it with?  I don't have any real access to much in the way of testing equipment...  The steel knife tip I tried the scratch test with, did leave a  pencil-like mark, but that rubbed away with my fingertip, with no indication of any actual scratching of the slab material.
Logged

bobby1

  • Full Member
  • ***
  • Offline Offline
  • Posts: 193
Re: Unknown... ?Agate, perhaps?
« Reply #8 on: January 20, 2019, 01:11:31 PM »

Could you show a photo of the fracture surface on the bottom?
Bob
Logged

Rosemaryr

  • Newbie
  • *
  • Offline Offline
  • Posts: 29
Re: Unknown... ?Agate, perhaps?
« Reply #9 on: January 20, 2019, 02:12:57 PM »

Could you show a photo of the fracture surface on the bottom?
Bob

Here's the best end shot I could get... using my camera, which doesn't have a great level of zoom.  Also, a shot of the two unknowns next to the two slabs of jade from the collection.  We had a break in the weather, so these shots are in outdoor lighting, unlike the previous which were indoor with overhead and flash lighting.  I did reduce the image size... I didn't want to overload the forum's limits.  I can post a full image, if needed..but it would be about 2 Mgs (2592x1944 pixels).
Logged

gemfeller

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 478
    • Art Cut Gems
Re: Unknown... ?Agate, perhaps?
« Reply #10 on: January 20, 2019, 05:01:38 PM »

This is just a WAG but it looks a lot like the hydrogrossular garnet rough I cut this cab from.  The hardness is right and so is the appearance.
Grossular.jpg
*Grossular.jpg (79.8 kB . 450x378 - viewed 113 times)
Logged

Rosemaryr

  • Newbie
  • *
  • Offline Offline
  • Posts: 29
Re: Unknown... ?Agate, perhaps?
« Reply #11 on: January 20, 2019, 08:50:14 PM »

This is just a WAG but it looks a lot like the hydrogrossular garnet rough I cut this cab from.  The hardness is right and so is the appearance.

That does look a lot like the stuff... especially compared to the second (wet) pic above.  I've seen some hydrogrossular garnet that is more spots and splotches, but your cab does have more of the swirled look.
Logged

Slabbercabber

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 346
Re: Unknown... ?Agate, perhaps?
« Reply #12 on: January 21, 2019, 06:52:35 AM »

It looks like Polar jade.  How about streak.

?  What would I use to test it with?  I don't have any real access to much in the way of testing equipment...  The steel knife tip I tried the scratch test with, did leave a  pencil-like mark, but that rubbed away with my fingertip, with no indication of any actual scratching of the slab material.

You can get a streak test using any rough ceramic such as cheap dinner plates or white knife sharpener.  The back of a ceramic tile is what I have on my bench.
Logged

Michael

  • Jr. Member
  • **
  • Online Online
  • Posts: 98
Re: Unknown... ?Agate, perhaps?
« Reply #13 on: January 21, 2019, 12:00:46 PM »

I purchased a nice piece of Polar (BC) jade at Quartzite QIA this week end.  These pictures look similar with what is called the "flame" component.  Good pictures.
Logged

Rosemaryr

  • Newbie
  • *
  • Offline Offline
  • Posts: 29
Re: Unknown... ?Agate, perhaps?
« Reply #14 on: January 22, 2019, 09:01:17 AM »

Quote
You can get a streak test using any rough ceramic such as cheap dinner plates or white knife sharpener.  The back of a ceramic tile is what I have on my bench.

It took me a while to find a suitable tile.  Tried it:  the unknown left no mark on the ceramic.  So, it could be either garnet or jade, according to the chart I found on-line.
Also tried a scratch test with a known piece of jade.  That was interesting.  The greener areas took no visible scratch, but the gray areas did.  The scratches were not perceptible to touch, but the marks would not rub away... they are indeed scratched into the surface.  So i am assuming that the grayer areas are not jade themselves, but some other material that looks gray when dry and green when wet.
Logged
Pages: [1] 2  All   Go Up
 

Page created in 0.102 seconds with 53 queries.