❓Your Mineral Identification Questions answered here

Prospecting Australia

Help Support Prospecting Australia:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Gilly47 said:
Went for a scratch in Retreat creek The Gemfields qld, wuz lookin for sapphires with no luck, then tripped over this fist size cooked rock. Gave it the vinegar soak.. Any ideas on what to use next. When it is cleaner I am hoping to see some sparkle in the small cavities, with the possibility of cutting in half and finding a geode.

Never been disappointed when out scratching, pink quartz, mica in quartz, black and brown quartz like a licorice allsort. keep the nose to the ground and something will jump out atcha

ray :gemstone: :rainbow: :gemstone: :100:

https://www.prospectingaustralia.co...4427/1583152155_cooked_rock_retreat_creek.jpg

pretty rock - would take a good polish. Is that a coral top centre?
 
Rockhunter62 said:
Looks like normal ironstone to me Rick.

Cheers

Doug

Not a lot of point in asking with things like this without (a) a well focussed photo, (b) hardness, (c) streak, and preferably (d) SG, none of which are difficult to do. Otherwise you will only get wild guesses, including from me.
 
lealucas79 said:

Various minerals I suspect but much looks like silica. Same comment as to Rockhunter 62, except that your photos are sharp. For example, hardness is highly diagnostic of sapphire - it will easily scratch quartz.
 
Thanks Goldierocks :)

Unfortunately I dont have any quartz but it scratches glass really easily if that gives you any more indications?
 
lealucas79 said:
Thanks Goldierocks :)

Unfortunately I dont have any quartz but it scratches glass really easily if that gives you any more indications?

No ,that does not really help. Really no quartz in your area?
 
lealucas79 said:
Thanks Goldierocks :)

Unfortunately I dont have any quartz but it scratches glass really easily if that gives you any more indications?

If you are new to this, do a search on "Series on identifying minerals" under my name. I have given extensive details on how to identify minerals by their properties (not all of these need to be done, but often one or two properties are quite diagnostic of a particular mineral - eg some scratch like soft cheese with a pocket-knife, others can scratch quartz, the combination of colour and streak can help (eg chalcopyrite is yellow but the powder is greeny-black).

And few people bother with specific gravity but it is easily determined with a $20 electronic balance and is often highly diagnostic. You need one accurate to 0.01g not 0.1 g, and that will take a specimen of 200g mass if necessary:

https://www.ebay.com.au/itm/100g-0-...m2f464a60a4:g:NSgAAOSwiiVbuESp&frcectupt=true

And good, in-focus photos like yours help others to help you. This can be done on a mobile phone using something like this (I bought the same for only $6 - it includes UV light which gives you an added property for some minerals).

https://www.ebay.com.au/itm/Clip-On...113910?hash=item2f450f9c76:g:TeEAAOSwUM5e53cq

Actually here is the same one for a third of the price:

https://www.ebay.com.au/itm/Clip-Mi...020678?hash=item5b78f00886:g:EoYAAOSwW4hfC6nh
 
Hi All!

I just joined in the hopes of finding out what on earth we have! Hubby stubbed his toe on it at an east coast beach 15-20 years ago and has been lugging it around since.

I see people talking about different terms to help identify specimens like hardness and gravity something but I'm a total newb and have no idea what this is about :awful:

Its quite hefty, like 9-10kgs at a guess?? We suspect it's some kind of crystal because of the opaque colour seen on the naturally shaven sides (as found).

Can anyone point me in the right direction on identifying this bigger??

Been wanting to crack the sucker open for years, but also don't want to do it incorrectly and potentially damage or ruin it :argh:

Cheers!

1597129159_user_scoped_temp_data_orca_share_media1597128480904_6698842375972979391.jpg


1597129187_user_scoped_temp_data_orca_share_media1597128481700_6698842379311850639.jpg


1597129351_user_scoped_temp_data_orca_share_media1597128483585_6698842387216885809.jpg
 
1600770917_4dfd098a-99a1-42ea-91b1-565408d0ae8a.jpg

1600770917_e957b0ba-32d1-4af1-80ed-84dce461404e.jpg

1600770917_e3253589-6130-4b51-9ae7-902166507b85.jpg

1600770917_f6f12c0a-8441-4d8d-bc66-7e4ff31e426c.jpg
Im not sure where I found this, Adelaide hills somewhere.... it had been hidden in my finds bag for awhile and when I cleaned it up I was pleasantly surprised to find this interesting nugget . I recall when I detected it I thought I had scored a gold nugget, purely on its weight, but when I saw its grey colour, just figured it was lead and threw it in the bag.
Here are a few properties:
Non magnetic
SG around 6
Streak....silver/grey
Metallic /greasy lustre
Hardness... around 4/5
It was reasonably hard to drill through (the swarthe was flaky/crystalline) and it left a shiny flat after filing.
Any ideas on what it may be ?
 
Seems a bit soft for an iron sulphide (which are usually around 6), and SG seems too high at 6 (should be 5) - also streak would usually be closer to dark grey to black. Is the flat surface on your last photo natural or filed?
 
I hear you guys are the experts on here. Found this and many others i believe them to be lava rocks/ dried lava some have metalic allows which have turned hard with them.
I read that gold and iron has been found with lava stone so i have ventured that direction at the moment.
Anyway.
I broke open 1 such rock yesterday.
Inside where the air pockets and holes normally are 1 has managed to have metal seem into them.
Maybe i will just let the pictured do the talking
 

Latest posts

Top