Welcome guest, is this your first visit?
Member
Discoveries
 
Results 1 to 13 of 13
Like Tree18Likes
  • 1 Post By HappyTrails55
  • 1 Post By Kray Gelder
  • 4 Post By Eu_citzen
  • 2 Post By HappyTrails55
  • 1 Post By IAMZIM
  • 2 Post By Eu_citzen
  • 2 Post By DDancer
  • 1 Post By HappyTrails55
  • 1 Post By IAMZIM
  • 2 Post By Eu_citzen
  • 1 Post By HappyTrails55

Thread: Can You Help I.D. this Rock

« Prev Thread | Next Thread »
  1. #1
    ca
    Sep 2005
    Paso Robles
    Teknetics G2
    257
    165 times

    Can You Help I.D. this Rock

    I kind of have my own thoughts about it but would be interested in hearing from the Professionals. I broke several pieces off of a 5 to 7 ton boulder on my claim, it scratches quartz no problem, is very hard, in fact the big sludge hammer I was using was a chore to get it to break, according to my Hardness Test Kit, it scratches with a # 9 pick....hope the pictures work, (there's clear crystal looking gemstones?) in the pink looking feldspars. I'm a thinking this could be Corundum with Saphhires, but I don't know for sure....Click image for larger version. 

Name:	101_3162.JPG 
Views:	41 
Size:	1.09 MB 
ID:	1532798Click image for larger version. 

Name:	101_3163.JPG 
Views:	51 
Size:	1.11 MB 
ID:	1532799Click image for larger version. 

Name:	101_3164.JPG 
Views:	44 
Size:	1.18 MB 
ID:	1532800Click image for larger version. 

Name:	101_3165.JPG 
Views:	43 
Size:	1.15 MB 
ID:	1532801Click image for larger version. 

Name:	101_3166.JPG 
Views:	61 
Size:	1.14 MB 
ID:	1532802Click image for larger version. 

Name:	101_3167.JPG 
Views:	46 
Size:	1.12 MB 
ID:	1532803Click image for larger version. 

Name:	101_3168.JPG 
Views:	29 
Size:	1.10 MB 
ID:	1532804Click image for larger version. 

Name:	101_3169.JPG 
Views:	29 
Size:	1.11 MB 
ID:	1532805Click image for larger version. 

Name:	101_3170.JPG 
Views:	37 
Size:	986.1 KB 
ID:	1532806Click image for larger version. 

Name:	101_3171.JPG 
Views:	28 
Size:	1.07 MB 
ID:	1532807Click image for larger version. 

Name:	101_3172.JPG 
Views:	28 
Size:	1.13 MB 
ID:	1532808Click image for larger version. 

Name:	101_3173.JPG 
Views:	30 
Size:	1.06 MB 
ID:	1532809
    Kray Gelder likes this.

  2. #2
    Charter Member
    us
    papa

    Feb 2017
    Georgetown, SC
    Fisher F75
    1,501
    1928 times
    Metal Detecting
    If it scratches a nine, it must be corundum. Nice specimen. Are you in Montana?


    Lying is now the norm. The truth is not only unwelcome, it is offensive.

  3. #3
    ca
    Sep 2005
    Paso Robles
    Teknetics G2
    257
    165 times
    Hi Kray, No, not in Montana, San Luis Obispo County, California

  4. #4
    Charter Member
    us
    papa

    Feb 2017
    Georgetown, SC
    Fisher F75
    1,501
    1928 times
    Metal Detecting
    Quote Originally Posted by HappyTrails55 View Post
    Hi Kray, No, not in Montana, San Luis Obispo County, California
    A quick search shows your county loaded with mines, none specifically for corundum. No reason why you wouldn't find some there, though. Seems to be mineral rich region.
    HappyTrails55 likes this.


    Lying is now the norm. The truth is not only unwelcome, it is offensive.

  5. #5
    se
    Sep 2006
    Sweden
    White's V3, Minelab Explorer II & XP Deus.
    6,248
    1884 times
    Prospecting
    Your rock looks like granitoid. My bet is on a pegmatite vein and you didn't apply enough force when using #8 on the hardness kit.
    Geologists are gneiss, tuff, and a little wacke.

  6. #6
    ca
    Sep 2005
    Paso Robles
    Teknetics G2
    257
    165 times
    Eu, hi and thanks for the response. I looked that granitoid up and read all about it, that may not be a bad thing if that's what it is. These are only pieces I broke off of this Big Boulder that is about 5 ' tall with a circumference of about 10 ', the clear crystal's are dominate in the pink feldspar but are everywhere in the boulder, like thousands or more that are visible. It certainly is surrounded by seyenite and nepheline granite and these granites certainly have very large quartz crystals intruded through the granites, metamorphic rock abounds everywhere with a lot of sedimentary as well. All of this sits on top of a Greenstone Belt Bed, which is where all of the gold and platinum comes from where we mine which is also on a cross/fault. I've done my homework on the platinum with assays from 2 highly reputable assayer's and collect platinum pieces up to 2.5 grain or 0.17 gram. But the issue here is this boulder that's in the way of the operation. So I started researching this corundum and watching everything I could and the G.I.A. has just wonderful youtube video's on sapphire found in seyenite and nepheline granites. I have one of these Diamond Selector II Lamp Detectors, I'll set it low on 3 and the crystals will run all the way up and past 8 to diamond (red light) beeping...so something is curious here, I have a friend in downtown Paso here that has his own Jewelry Shop with a Spectrometer and today I'm going go see him and get the skinny on this and then report back, Thanks
    stdenis_jd and BIGSCOTT like this.

  7. #7
    us
    Jason

    Apr 2011
    Butte City, Montana
    ace 250/garret pinpointer, garret AT Gold
    1,272
    1511 times
    All Types Of Treasure Hunting
    Quote Originally Posted by HappyTrails55 View Post
    Eu, hi and thanks for the response. I looked that granitoid up and read all about it, that may not be a bad thing if that's what it is. These are only pieces I broke off of this Big Boulder that is about 5 ' tall with a circumference of about 10 ', the clear crystal's are dominate in the pink feldspar but are everywhere in the boulder, like thousands or more that are visible. It certainly is surrounded by seyenite and nepheline granite and these granites certainly have very large quartz crystals intruded through the granites, metamorphic rock abounds everywhere with a lot of sedimentary as well. All of this sits on top of a Greenstone Belt Bed, which is where all of the gold and platinum comes from where we mine which is also on a cross/fault. I've done my homework on the platinum with assays from 2 highly reputable assayer's and collect platinum pieces up to 2.5 grain or 0.17 gram. But the issue here is this boulder that's in the way of the operation. So I started researching this corundum and watching everything I could and the G.I.A. has just wonderful youtube video's on sapphire found in seyenite and nepheline granites. I have one of these Diamond Selector II Lamp Detectors, I'll set it low on 3 and the crystals will run all the way up and past 8 to diamond (red light) beeping...so something is curious here, I have a friend in downtown Paso here that has his own Jewelry Shop with a Spectrometer and today I'm going go see him and get the skinny on this and then report back, Thanks
    Intrested to hear what you find! Something you may want to take note of is, hardness on a specimen is not always going to give you a definite answer, sometimes more tests can be needed. A case in point: I had what I was sure was a topaz because of using the hardness test on it, after testing myself, then taking it to the mining museum here in my town and having three geologists test the hardness, even they thought it was topaz, but after a refraction test, and the XRF test, as well as others, it turned out to be quartz, an unusually hard piece of quartz! Even the guy I had facet the stone said it seemed like he was cutting topaz or something harder than quartz! Only reason I bring this up is, you may need other tests to accompany the hardness test! The other thing you need to consider is the presence of many different minerals in your one stone. Right away I see what looks like Potassium Feldspar, and Quartz, which have differing hardness. Then you have the red looking rock, could be garnet, or, could be corundum, or it could just be iron stained quartz. There could be many other minerals in that rock besides! You definitely may need several tests!
    Last edited by IAMZIM; Jan 02, 2018 at 02:19 PM.
    HappyTrails55 likes this.

  8. #8
    se
    Sep 2006
    Sweden
    White's V3, Minelab Explorer II & XP Deus.
    6,248
    1884 times
    Prospecting
    Quote Originally Posted by HappyTrails55 View Post
    Eu, hi and thanks for the response. I looked that granitoid up and read all about it, that may not be a bad thing if that's what it is.
    These are only pieces I broke off of this Big Boulder that is about 5 ' tall with a circumference of about 10 ', the clear crystal's are dominate in the pink feldspar but are everywhere in the boulder, like thousands or more that are visible.
    It certainly is surrounded by seyenite and nepheline granite and these granites certainly have very large quartz crystals intruded through the granites, metamorphic rock abounds everywhere with a lot of sedimentary as well.
    All of this sits on top of a Greenstone Belt Bed, which is where all of the gold and platinum comes from where we mine which is also on a cross/fault.
    I've done my homework on the platinum with assays from 2 highly reputable assayer's and collect platinum pieces up to 2.5 grain or 0.17 gram. But the issue here is this boulder that's in the way of the operation.
    So I started researching this corundum and watching everything I could and the G.I.A. has just wonderful youtube video's on sapphire found in seyenite and nepheline granites.
    I have one of these Diamond Selector II Lamp Detectors, I'll set it low on 3 and the crystals will run all the way up and past 8 to diamond (red light) beeping...so something is curious here, I have a friend in downtown Paso here that has his own Jewelry Shop with a Spectrometer and today I'm going go see him and get the skinny on this and then report back, Thanks
    Syenite, pegmatites are certainly something to keep an eye out in your area.
    In the pegmatites, look for crystals, they often sit in pockets.

    Diamondtesters should be taken with a barrel full of salt. They can be inaccurate in these situations.
    Geologists are gneiss, tuff, and a little wacke.

  9. #9
    us
    Mar 2014
    Traveling US to work
    Current Whites DFX Past Garret GTI 2500 and others Prospecting Minelab GPZ 7000 Past SD 2100 GP 3000 (retired)
    1,878
    1391 times
    Metal Detecting
    I support what IAZIM and EU have to say about the composition, though I feel its garnet for the reds, and hardness as a test. I'll add that hardness tests should be used as an indication to narrow down a minerals hardness and not an indication of maximum hardness. What I mean is that if I use a 6, 7 and 8 and get a scratch indication at 8 then the hardness is between 7 and 8. With the mix of minerals you have you should have various hardness's for individual sample sites. The various cleavages and fractures of the minerals also lends to the identifications IAMZIM and EU have pointed out. Depending on the way a crystal forms it can have a morphed, changed/folded/twinned, layering and register harder than a normal crystal would register in a hardness test. Something IAMZIM pointed out as an example with quartz.
    Diamond testers are, well, for diamonds and cut gems that simulate diamonds and only give a simple indication via the use of thermal conductivity. If metalics are present in a sample they can register higher conductivity and result in false positives. Careful inspection, and in the case of clear specimens refractive testing, are more positive ways of identifying diamond.
    As EU indicated look for pockets in the pegmatites There are a few members here showing some nice prizes from such pockets.
    My thoughts.

    Addendum. I for one an happy you included a hardness test with you original post. It helps and the pictures were well done
    Last edited by DDancer; Jan 03, 2018 at 09:09 AM.
    IAMZIM and HappyTrails55 like this.
    Everyone Believes they have gold buried in the back yard... small wonder so few ever look for it.

  10. #10
    ca
    Sep 2005
    Paso Robles
    Teknetics G2
    257
    165 times
    Thank you DDancer and everyone else for the Input. I went to my friend, the Jeweler but as it turned out he was not receptive to my visit, told me his Spectrometer had bit the dust although I did see it in his store, so I just wished him a Happy New Year and left...I certainly enjoy reading here the input and advice and will log it into my memory banks. Some gemological testing certainly needs to be done which could run into some money and ofcourse time. Since the majority of the larger crystals of this rock is encased within the pink feldspar, I experimented with some small chisels and so far have found out that the feldspar is somewhat easily dislodged from this other part of the rock. after some further research I ordered a JoolTool from Amazon as well as Gem Eye Digital Refractometer from Mineralabs, both about $400 each or less than $1,000 bucks....Not knowing how much I would spend on gemological tests, I just figured it out that it would basically just cost me 1 ounce of gold, which I can easily afford...Both machines would just be a asset to the already growing tool chest...I don't really care about damaging any of these crystal stones coming out of the rock, it's the knowledge I want, if these stones are something of value then apparently they are in the placers as well and us gold miners are throwing them away....So I decided I'd run my own tests for now 1st using the jooltool to get a good grinded base on the crystals and then analyze them with the Computer Refractometer from Mineralabs...I'll definitely be a looking for the pockets too...These 3 pictures here were taken last week from one of my claim partners with my camera, the shutter did not open all of the way. On the right is me digging around this granite pegamite and just to the left is the Big Boulder, about 5 to 8 feet awayClick image for larger version. 

Name:	101_3157.JPG 
Views:	51 
Size:	1.00 MB 
ID:	1533775Click image for larger version. 

Name:	101_3158.JPG 
Views:	50 
Size:	1.01 MB 
ID:	1533776Click image for larger version. 

Name:	101_3159.JPG 
Views:	43 
Size:	1,008.6 KB 
ID:	1533777
    stdenis_jd likes this.

  11. #11
    us
    Jason

    Apr 2011
    Butte City, Montana
    ace 250/garret pinpointer, garret AT Gold
    1,272
    1511 times
    All Types Of Treasure Hunting
    Question: are you working a placer deposit, and is that where you found this particular rock? If so, I would think that if there were any gemstones in the area that you should be finding them panning or sluicing, or whatever method you are using. Sapphires, garnets, and diamonds are all heavy enough to show up with your gold, so that is where I would make the effort to look for them if that is what you are trying to target. Otherwise, your rock, being a piece of pegmatite, is an indicator of a pegmatite (I know the way I am saying this seems weird) that could be worth exploring. What you want to look for is more pegmatite, to search for either fissures or vugs (a hollow where a gas bubble formed in the magma) and that is where you would be most likely to encounter your crystal pockets that would have the potential for gems like beryls or other minerals. I see you are from California, I don't know the area you are, but I do know that California has tourlamine, which is also what could be in that piece of peg you have posted. As far as panning beryl or tourmaline, I don't know a lot about tourmaline as far as weight, but beryls wont show up in the bottom of your pan because they are too light. I look forward to see whatever you find!
    HappyTrails55 likes this.

  12. #12
    se
    Sep 2006
    Sweden
    White's V3, Minelab Explorer II & XP Deus.
    6,248
    1884 times
    Prospecting
    Quote Originally Posted by HappyTrails55 View Post
    Thank you DDancer and everyone else for the Input. I went to my friend, the Jeweler but as it turned out he was not receptive to my visit, told me his Spectrometer had bit the dust although I did see it in his store, so I just wished him a Happy New Year and left...I certainly enjoy reading here the input and advice and will log it into my memory banks. Some gemological testing certainly needs to be done which could run into some money and ofcourse time. Since the majority of the larger crystals of this rock is encased within the pink feldspar, I experimented with some small chisels and so far have found out that the feldspar is somewhat easily dislodged from this other part of the rock. after some further research I ordered a JoolTool from Amazon as well as Gem Eye Digital Refractometer from Mineralabs, both about $400 each or less than $1,000 bucks....Not knowing how much I would spend on gemological tests, I just figured it out that it would basically just cost me 1 ounce of gold, which I can easily afford...Both machines would just be a asset to the already growing tool chest...I don't really care about damaging any of these crystal stones coming out of the rock, it's the knowledge I want, if these stones are something of value then apparently they are in the placers as well and us gold miners are throwing them away....So I decided I'd run my own tests for now 1st using the jooltool to get a good grinded base on the crystals and then analyze them with the Computer Refractometer from Mineralabs...I'll definitely be a looking for the pockets too...These 3 pictures here were taken last week from one of my claim partners with my camera, the shutter did not open all of the way. On the right is me digging around this granite pegamite and just to the left is the Big Boulder, about 5 to 8 feet awayClick image for larger version. 

Name:	101_3157.JPG 
Views:	51 
Size:	1.00 MB 
ID:	1533775Click image for larger version. 

Name:	101_3158.JPG 
Views:	50 
Size:	1.01 MB 
ID:	1533776Click image for larger version. 

Name:	101_3159.JPG 
Views:	43 
Size:	1,008.6 KB 
ID:	1533777
    You're getting ahead of yourself. A refractometer is also used only on polished stones.
    So unless you got a lapidary machine to polish them, you're no closer to ID'ing them then yesterday.
    Learn the basic stuff; hardness testing and the other visual clues, specific gravity is also helpful if you can get of a clean piece.
    Geologists are gneiss, tuff, and a little wacke.

  13. #13
    ca
    Sep 2005
    Paso Robles
    Teknetics G2
    257
    165 times
    a Jooltool is a polishing machine
    Eu_citzen likes this.

 

 

Remove Ads

Sponsored Links

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Similar Threads

  1. Replies: 0
    Last Post: Sep 05, 2017, 03:08 PM
  2. Replies: 16
    Last Post: Jul 17, 2017, 06:54 AM
  3. Replies: 13
    Last Post: Sep 12, 2013, 07:40 PM
  4. Large heavy rock, possibly ancient anchor rock
    By Larry49934 in forum What Is It?
    Replies: 6
    Last Post: May 24, 2012, 02:07 AM
  5. Replies: 7
    Last Post: Apr 28, 2010, 01:04 PM
Powered by vBadvanced CMPS v4.3.0