We use cookies to show content based on your preferences. If you continue to browse you accept their use and installation. More information. >

FMF - Friends of Minerals Forum, discussion and message board
The place to share your mineralogical experiences


Spanish message board






Newest topics and users posts
02 Aug-10:20:30 Re: stay at home - coronavirus / covid-19 (Roger Warin)
02 Aug-09:15:31 Re: collection of michael shaw (Michael Shaw)
02 Aug-00:58:34 Re: stay at home - coronavirus / covid-19 (Peter Lemkin)
01 Aug-14:31:32 Re: stay at home - coronavirus / covid-19 (Don Lum)
01 Aug-14:24:20 Re: stay at home - coronavirus / covid-19 (Riccardo Modanesi)
01 Aug-14:21:52 Re: collection of sante celiberti (Jordi Fabre)
01 Aug-09:27:00 Re: corona covid-19 virus - what is it ? where is it from ? (Roger Warin)
01 Aug-07:15:53 Re: collection of volkmar stingl (Volkmar Stingl)
01 Aug-06:48:22 Re: corona covid-19 virus - what is it ? where is it from ? (Peter Lemkin)
01 Aug-04:45:19 Re: corona covid-19 virus - what is it ? where is it from ? (R Saunders)
31 Jul-22:40:40 Corona covid-19 virus - what is it ? where is it from ? (Roger Warin)
31 Jul-16:32:56 Re: collection of firmo espinar (Firmo Espinar)
30 Jul-14:58:22 Re: melanophlogite? (Luiz Oliveira)
30 Jul-14:51:23 Re: about a rutile epitaxy on hematite in quartz (Roger Warin)
30 Jul-03:36:43 The mizunaka collection - quartz (Am Mizunaka)
29 Jul-22:49:31 Re: collection of volkmar stingl (Volkmar Stingl)
29 Jul-21:35:18 Re: about a rutile epitaxy on hematite in quartz (Alfredo)
29 Jul-14:10:03 Re: collection of michael shaw (Michael Shaw)
28 Jul-21:29:06 Re: about a rutile epitaxy on hematite in quartz (Roger Warin)
28 Jul-21:24:20 Re: unknown quartz? (Steveb)
28 Jul-21:23:26 About a rutile epitaxy on hematite in quartz (Roger Warin)
28 Jul-15:43:19 Unknown quartz? (R Saunders)
28 Jul-13:15:33 Re: collection of volkmar stingl (Volkmar Stingl)
27 Jul-22:43:51 Re: collection of volkmar stingl (Volkmar Stingl)
27 Jul-13:17:17 Re: celestite geode in dolomite block? or what, halite? (Don Lapham)

For lists of newest topics and postings click here


RSS RSS

View unanswered posts

Why and how to register

Index Index
 FAQFAQ RegisterRegister  Log inLog in
 {Forgotten your password?}Forgotten your password?  

Like
83992


The time now is Aug 02, 2021 15:59

Search for a textSearch for a text   

A general guide for using the Forum with some rules and tips
The information provided within this Forum about localities is only given to allow reference to them. Any visit to any of the localities requires you to obtain full permission and relevant information prior to your visit. FMF is strictly against any illicit activities related to collecting minerals.
Please help to get to know the type of this rock
  
  Index -> What is it? - Where is it from?
Like
3


View previous topic :: View next topic  
Author Message

Majid




Joined: 05 Apr 2021
Posts: 7

View user's profile

Send private message

PostPosted: Apr 05, 2021 14:35    Post subject: Please help to get to know the type of this rock  

Hello all
This is my first participation in this wonderful forum. I am interested in precious stones. I have a very solid black stone in my possession. I thought it was a meteor at the beginning But when I experimented with scratching the stone with quartz and sapphire, the stone wasn't even scratched with sapphire Could it be a black diamond?
Please help me Thank you all.

Back to top
This topic is locked: you cannot edit posts or make replies. Reply with quote
Like
1
   

Bob Carnein




Joined: 22 Aug 2013
Posts: 245
Location: Florissant, CO


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Apr 05, 2021 16:01    Post subject: Re: Please help to get to know the type of this gem  

Can you tell us where you found it or how you acquired it? Offhand, it looks like a tektite; If you use a strong light, is it all translucent? If so, what color is it? Did you reverse the hardness test and try to scratch quartz or sapphire with it? (Hardness tests are tricky because some stones are brittle and crumble, which is not the same as scratching.)
Back to top
This topic is locked: you cannot edit posts or make replies. Reply with quote
Like
1
   

Majid




Joined: 05 Apr 2021
Posts: 7

View user's profile

Send private message

PostPosted: Apr 05, 2021 16:06    Post subject: Re: Please help to get to know the type of this gem  

Bob Carnein wrote:
Can you tell us where you found it or how you acquired it? Offhand, it looks like a tektite; If you use a strong light, is it all translucent? If so, what color is it? Did you reverse the hardness test and try to scratch quartz or sapphire with it? (Hardness tests are tricky because some stones are brittle and crumble, which is not the same as scratching.)
.I found it in the desert, it is not transparent at all, it is dark even if you shine a light on it. I tried to scratch it on a piece of synthetic sapphire and the result was not affected by the scratch
Back to top
This topic is locked: you cannot edit posts or make replies. Reply with quote
Like
   

Michael Krug




Joined: 21 May 2020
Posts: 9
Location: Allendorf / Lumda

View user's profile

Send private message

PostPosted: Apr 06, 2021 05:59    Post subject: Re: Please help to get to know the type of this gem  

Hello,
I'm pretty sure it's volcanic slag (obsidian?). This is my find (700g) from a Canary Island (La Palma).
An ejection in the form of a drop? The white inclusion is a quartz.
Glück auf!
Michael



P4060091 (2).JPG
 Mineral: Obsidian (?)
 Description:
shore
100 mm x 85 mm
 Viewed:  1685 Time(s)

P4060091 (2).JPG


Back to top
This topic is locked: you cannot edit posts or make replies. Reply with quote
Like
   

Michael Krug




Joined: 21 May 2020
Posts: 9
Location: Allendorf / Lumda

View user's profile

Send private message

PostPosted: Apr 06, 2021 06:02    Post subject: Re: Please help to get to know the type of this gem  

overall view


P4060089 (2).JPG
 Mineral: Obsidian (?)
 Description:
shore
 Viewed:  1680 Time(s)

P4060089 (2).JPG


Back to top
This topic is locked: you cannot edit posts or make replies. Reply with quote
Like
   

Majid




Joined: 05 Apr 2021
Posts: 7

View user's profile

Send private message

PostPosted: Apr 06, 2021 06:04    Post subject: Re: Please help to get to know the type of this gem  

Michael Krug wrote:
Hello,
I'm pretty sure it's volcanic slag (obsidian?). This is my find (700g) from a Canary Island (La Palma).
An ejection in the form of a drop? The white inclusion is a quartz.
Glück auf!
Michael
Hi .
I have a question, what is the highest degree of hardness for slag.
Back to top
This topic is locked: you cannot edit posts or make replies. Reply with quote
Like
   

Peter Lemkin




Joined: 18 Nov 2016
Posts: 341
Location: Prague

View user's profile

Send private message

PostPosted: Apr 06, 2021 06:22    Post subject: Re: Please help to get to know the type of this gem  

Glass slag is hardness 7, but there are exotic industrial slags with higher hardness.
You have come up at first with two very unlikely ideas: meteorite, and even more unlikely diamond. If it is not slag it could be a tectite. You say in the desert, but not which desert. Please be exact. And please again do a hardness test and if you can a specific gravity test [instructions on this website]. No black diamonds that size and even a small one is very unlikely to be found in any desert I know of. Meteorites are rare and don't usually have that kind of suface feature unless they are metallic - that doesn't look metallic, it looks 'glassy'. While one can get lucky, too many assume [hope] their find is not just an ordinary stone, but an extraordinary one. Do the tests and tell the exact location, and maybe we can help. How far in the desert from developed industry or housing and what desert?
Back to top
This topic is locked: you cannot edit posts or make replies. Reply with quote
Like
   

James Catmur
Site Admin



Joined: 14 Sep 2006
Posts: 856
Location: Cambridge


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Apr 06, 2021 06:28    Post subject: Re: Please help to get to know the type of this gem  

Check the specific gravity, not the weight (the weight tells us nothing, except that it weighs something)

https://www.mineral-forum.com/message-board/viewtopic.php?p=38375#38375

James
Back to top
This topic is locked: you cannot edit posts or make replies. Reply with quote
Like
   

Michael Krug




Joined: 21 May 2020
Posts: 9
Location: Allendorf / Lumda

View user's profile

Send private message

PostPosted: Apr 06, 2021 06:55    Post subject: Re: Please help to get to know the type of this gem  

You are right, James.
With a rough method (kitchen measuring glass) I measure: 3,5 g/ccm
Back to top
This topic is locked: you cannot edit posts or make replies. Reply with quote
Like
   

Peter Lemkin




Joined: 18 Nov 2016
Posts: 341
Location: Prague

View user's profile

Send private message

PostPosted: Apr 06, 2021 07:11    Post subject: Re: Please help to get to know the type of this gem  

I just noticed you put it up on Youtube and labeled it a black diamond! And you [on your second try after a moderator closed your first thread] come back and still call it a 'gem'. Whatever it is, it is not a gem, sorry, and this forum doesn't deal in gems. Careful, you could be heading toward another closed thread unless you ASK and follow advice, and don't just ASSUME. Please follow the suggestions for tests and give location. How heavy is it compared to known objects of that size [metal, glass, water, wood]. A specific gravity test is what is really needed and a very well done hardness test. My guess without enough information remains slag or tectite or sandblasted glass in the desert.
Back to top
This topic is locked: you cannot edit posts or make replies. Reply with quote
Like
   

Majid




Joined: 05 Apr 2021
Posts: 7

View user's profile

Send private message

PostPosted: Apr 06, 2021 07:32    Post subject: Re: Please help to get to know the type of this rock  

Peter Lemkin wrote:
I just noticed you put it up on Youtube and labeled it a black diamond! And you [on your second try after a moderator closed your first thread] come back and still call it a 'gem'. It is not a gem whatever it is,sorry, and this forum doesn't deal in gems. Careful, you could be heading toward another closed thread unless you ASK and follow advice, and don't just ASSUME. Please follow the suggestions for tests and give location. How heavy is it compared to known objects of that size [metal, glass, water, wood]. A specific gravity test is what is really needed and a very well done hardness test. My guess without enough information remains slag or tectite or sandblasted glass in the desert.
I put a title on YouTube, black diamonds, not for promotion. I did not offer them for sale, but because I suspect them about diamonds. In either case, I will do the required tests and provide you with the details. Thank you for your attention.
Back to top
This topic is locked: you cannot edit posts or make replies. Reply with quote
Like
   

James Catmur
Site Admin



Joined: 14 Sep 2006
Posts: 856
Location: Cambridge


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Apr 06, 2021 09:38    Post subject: Re: Please help to get to know the type of this rock  

Hit it with a hammer and see what the cleavage is.
Back to top
This topic is locked: you cannot edit posts or make replies. Reply with quote
Like
1
   

Matt_Zukowski
Site Admin



Joined: 10 Apr 2009
Posts: 660
Location: Alaska


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Apr 06, 2021 23:08    Post subject: Re: Please help to get to know the type of this rock  

Honestly, there is nothing about this rock that suggests diamond to me. I would be very surprised if your hardness test was accurate. My advice to you is that you should stop trying to convince us that it is a diamond and instead go to the geology department at the nearest university and show it to them.
Back to top
This topic is locked: you cannot edit posts or make replies. Reply with quote
Like
   

Jordi Fabre
Overall coordinator of the Forum



Joined: 07 Aug 2006
Posts: 4685
Location: Barcelona


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Apr 07, 2021 02:28    Post subject: Re: Please help to get to know the type of this rock  

Peter Lewmkin wrote:
And you [on your second try after a moderator closed your first thread] come back and still call it a 'gem'. Whatever it is, it is not a gem, sorry, and this forum doesn't deal in gems.

Matt_Zukowski wrote:
Honestly, there is nothing about this rock that suggests diamond to me. I would be very surprised if your hardness test was accurate. My advice to you is that you should stop trying to convince us that it is a diamond and instead go to the geology department at the nearest university and show it to them.

Absolutely.

Majid, this is a scientific Forum. You already have all answers you can get for your, two times, equal requests. Please don't repeat the same request again and again and with the same lack of scientific evidences.

Topic locked (again)
Back to top
This topic is locked: you cannot edit posts or make replies. Reply with quote
Like
   
Display posts from previous:   
   Index -> What is it? - Where is it from?   All times are GMT - 5 Hours
Page 1 of 1
    

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum


All pictures, text, design © Forum FMF 2006-2021


Powered by FMF