❓Your Mineral Identification Questions answered here

[LONEWOLF]

Re the grinder... Be very careful and wear eye protection... Using a thin blade there is more chance of something going wrong as you only need a slight wobble and the blade may shatter.... And Wear a dust mask as some dust from Rocks is very Toxic such as Quartz.. It contains Silica and that is far worse than Asbestos... Silicosis is the result of breathing Quartz Dust... And your rock has Quartz in it I think.....

LW...

 

[Icebirth]

Re the grinder... Be very careful and wear eye protection... Using a thin blade there is more chance of something going wrong as you only need a slight wobble and the blade may shatter.... And Wear a dust mask as some dust from Rocks is very Toxic such as Quartz.. It contains Silica and that is far worse than Asbestos... Silicosis is the result of breathing Quartz Dust... And your rock has Quartz in it I think.....

LW...

Thanks LW, you raise an important point that I only became aware of myself a few days ago when a friend said the same thing. I had no idea Quartz dust was so dangerous.

I'm rethinking cutting them now. But they're bloody huge and weigh like 5-10 kg each, I'm not sure exactly what else to do with them.

 

[LONEWOLF]

You still can cut them, Do you have any Brick layers working in your area, they may be able to cut it on their Brick saw... Or stick with your Method of using a Masonry blade in your Grinder... Just wear your PPE... Being so big it would make a great doorstop...

LW.....

 

[user 4386]

Re the grinder... Be very careful and wear eye protection... Using a thin blade there is more chance of something going wrong as you only need a slight wobble and the blade may shatter.... And Wear a dust mask as some dust from Rocks is very Toxic such as Quartz.. It contains Silica and that is far worse than Asbestos... Silicosis is the result of breathing Quartz Dust... And your rock has Quartz in it I think.....

LW...

Thanks LW, you raise an important point that I only became aware of myself a few days ago when a friend said the same thing. I had no idea Quartz dust was so dangerous.

I'm rethinking cutting them now. But they're bloody huge and weigh like 5-10 kg each, I'm not sure exactly what else to do with them.

The advice is good, but with proper precautions any risk is negligible (I have been cutting rocks for 50 years, but always with good equipment). The main thing is not to create dry dust - a good saw sprays water onto the point of cutting, so no dust goes into the air for you to breathe in (but a simple dust mask - ie pad with elastic to hold it on)-is a good idea. Silica is not strictly "toxic" (i.e. it is not poisonous), but any dust is an irritant to the lungs, and can cause build up of crap in your lungs' airsacks (silicosis) - which can ultimately be deadly for miners and professional masons). The same is true of any type of hard dust (or coal) - not as dangerous as asbestos by a long shot (asbestos is fibrous and penetrates the walls of the airsacks as if the fibres were needles, and not only blocks the lungs but can irritate the cell walls and produce cancer. I cut up to about 30 cm blocks, but have different size saws depending on size (starting with a big saw then using smaller saws as I reduce). My blades are not brittle, they are copper or copper-rimmed steel I think, with diamonds impregnating the rim (a bit expensive). I have NEVER had one break or shatter in 50 years or seen anyone else have this issue - but common sense suggests that some protection is desirable. You are more likely to be hit by a piece of shattering rock than by a piece of blade (but again, I have never encountered such an injury). The usual worst problem is that if you feed it too rapidly into the blade, the saw jams - the rock can then fragment (usually just crumbles) and the blade can warp and become unusable (costly). Wear heavy work gloves (the blades are not sharp, they grind, but it protects from abrasion).

I have never used blades made of anything brittle (eg ceramic) and I would be wary of doing so.

One method is to get a monumental mason to cut any really large ones down to a size you can handle (I have done that with some 30 cm or more in diameter).

 

[Hunting the yellow]

(I posted this earlier but I think it was in the wrong section.)

Hi all,

I recently found some rocks and crystals I was hoping you all could help to identify.

The first is a stone with a dark blue tinge:
https://www.prospectingaustralia.com/forum/img/member-images/14708/1551151584_php8mmn92pm.jpg

Second, a big heavy whitish rock:
https://www.prospectingaustralia.com/forum/img/member-images/14708/1551151610_phpgxcn85pm.jpg

With this last one, Google image search kept saying it was Turkish bread:
https://www.prospectingaustralia.com/forum/img/member-images/14708/1551151764_20190226_140255.jpg

Any help would be appreciated, thank you .

Regards,
Ky.

top one blue ish looks very much like a mineral called clinochlore Google it if you want to see photos others are common milky quartz crystals.

 

[Hunting the yellow]

https://www.prospectingaustralia.com/forum/img/member-images/13421/1535238455_img_0002.jpgHi all, as you can notice I'm new to the forum and yesterday while out prospecting I found this in the pan (avatar picture )
It has 4 sides on each point with 4 flat sides.
I have no idea about crystals so any info would be appreciated.

quartz rock crystal double terminated very interesting as double terminations are rare however I have found many before at a placed called Mooralla Vic but they are Smokey quartz not clear rock crystal.

 

[tailormarc]

Hey guys now im pretty good as sussing different metals out but this one has got me wondering what it is....
Found in a location that has items no later than 1915 and goes back as early as 1860

Now its ....

Quite Magnetic
Hard as (not lead)
Not Galena
Dont think its tin as this is really magnetic,
Dont think its silver as its magnetic and doesnt give off the egg smell when rubbed with foil
Not pewter as its magnetic
Has a shiny crystalline structure and been out in elements over 100yrs so no iron or it would be rusted like the other stuff ive found

 

[Rockhunter62]

Someone wasn't trying to make chrome vanadium tools were they? Looks similar.

Cheers

Doug

 

[tailormarc]

Someone wasn't trying to make chrome vanadium tools were they? Looks similar.

Cheers

Doug

Not to sure what era that would be but this would of been made around 1860-1915 max. Area locked off with no one on it since then

 

[Rockwall]

These sounded like gold and are heavy on the hand like gold but.... In a red mineralised area with one being a foot or so down. Magnet ignores them. Using a gpz.

 

[Dihusky]

MartyZ came over a couple of weekends ago with some interesting stones, when here was here I SG tested them all as a starting point to try and identify what they are, since then a bunch more tests have been done and we are pretty much still at square 1, we have absolutely no clue as to this mineral's identity.

The first three photos are the rocks as one see's them in normal light, the clutch of stones are the sort of stone that would catch your eye in a sieve, then the next two are a more detailed study of the larger 12.95ct stone showing the fracture structure, which I think would be referred to a random, it doesn't appear to show ant distinct fracture planes, but better and more experienced eyes can correct me on this.

Then we added light, and wow the colour is amazing, first pic is the big stone:

These are the SG results for the stones: The large 12.95ct stone is 3.364, the smaller sones are 3.3, 3.24, 3.46 and two at 3.5 so there is a fair bit of variation, that said my scales only go down to 0.5ct so smaller stones will never be super accurate.

Moh is in the order of 6.5 as quartz (7) will scratch but Labradorite/Feldspar (6-6.5) wont scratch.

Streak test is white and the stones do not respond to 365nm UV, neither are they radioactive as one of our earlier suspicions was a type of Ekanite which contains Thorium, so this had to be eliminated.

We are now at a complete loss as to what these are. MartyZ will add some more info.

Over to the Brains trust for ideas please as we are out of them and can find nothing that fits and I think both of us anve spent many hours on the net researching.
Maybe we have a new discovery; "Zivianite" or "Ziviahuskite" ??

 

[Martyz]

Nice photos Dihusky. The rough photographs well but the cut stone is where we are heading if only we can put a name to it hey.
Here are some photos of a specimen I found that contains the crystal still contained within the surrounding basalt. A large decomposing basalt formation is situated only a few kilometres upstream from where the stones were found.

 

[Wally69]

There are certain aspects that make me think volcanic glass ; obsidian. Regionally unique trace elements could be producing the colouring.

Although the SG seems to be on the high side.

 

[user 4485]

Dravite (brown) tourmaline?

 

[Martyz]

Thanks Wally and mbasko.
Dihusky has done the testing (except the radioactive Thorium test) and apart from Ekanite, which we can now discount, Dravite may seem to be a new possibility. I did find what appeared to be black Tourmaline crystal in the area. SG is in the ball park and we could double check the hardness test. Google images shows Dravite specimens of similar colour and fracture characteristics.
What do you reckon Dihusky?

 

[Dihusky]

Unsure about Tourmaline, which has a Moh of around 7 - 7.5 and I don't see any of the classic Tourmaline crystal structure, Obsidian is an interesting suggestion though and I gather is not uncommon in the Darling Downs. Obsidian tends to have a lower Moh, but I imagine that depends on the specific mineral content.

 

[user 4386]

SG too high (if accurate), hardness slightly too low, conchoidal fracture a bit strong for tourmaline (which otherwise would definitely have been my guess - be sure re SG as it is the main one excluding tourmaline completely). Appears to show crystal faces, which excludes obsidian.

A clearer, more in-focus photo of the above might help. One completely blurred crystal? looks vaguely trigonal (as in tourmaline)

 

[Dihusky]

Thanks for the input Goldierocks, the SG is accurate, I have measured it several times on different days to make absolutely sure, and always come back with the same figures. I'll see what I can do about a better shot of the pebble.

 

[user 4485]

that said my scales only go down to 0.5ct so smaller stones will never be super accurate.

Did you try the SG with lower increment scales? Tourmaline SG is 2.8 to 3.3 so it's getting close?
Goldierocks - I did some research & found some suggestion that tourmaline is anisotropic or can display different properties (like hardness) in different directions? Not sure if this could be enough variance to allow quartz to scratch it one way?
Also if both are 7 mohs could quartz scratch it giving the impression its <7 but really 7 mohs too?
Not trying to make tourmaline the "winner" but anything else seems to far away in the SG, hardness etc. Maybe it is Zivianite"or "Ziviahuskite"

 

[Martyz]

Sorry about the quality of my photos. They are taken on an iPhone looking through a loupe. I will try and get a more detailed shot of that crystal and some other samples I have. Most of the specimens of crystal still contained within basalt seem to be heavily fractured so Im not sure how representative they are of a properly formed crystal. The larger gem quality specimens came from alluvial gravels in a creek bed and have undergone significant weathering.