stone ID

[willo1]

Hi everyone,
found these stones in a bucket of wash that was brought home for me by a mate. I know that one of the stones has a number of blue sapphire chips in it as well as bronze coloured chips which appear to be similar to the stone in the other pic. If anyone knows what the bronze coloured stone could be it would be greatly appreciated. Both stones do not appear to have any colours showing unless under a light.

Jason.

just showing the size of the stones. The bottom stone has the sapphire chips in it. The top stone is a bronze colour under light.

Bottom stone under light with the blue and bronze colours showing.

Top stone without any light.

Same stone under a light.

 

[shivan]

I would be thinking along the lines of Spinel or Corundum ( the mineral name for sapphires). Someone with a bit more knowledge may have a better idea.

 

[AtomRat]

Possibly corundum but yes, hard to tell

 

[M3talmiliti4]

Could that bottom one be zircon? Maybe?

Zircon always seems to be more water worn then sapphire being that it is softer, and that one seems to have more rounded edges then the bit of corundum

 

[silver]

Partie colored.

 

[Heatho]

Stone under the 5c piece is a Sapphire, not Sapphire chips. With the light under it I can 100% say it's a Sapphire.

The top one that is the browney yellow under light could be Sapphire as well. Kind of hard to tell. I've got quite a few this colour too.

Neither are gem quality.

 

[willo1]

Thanks for the input everyone. I know that neither are gem quality but was just more interested about what the bronze stone could have been. I think I will put it down as a low quality corundum....

 

[shivan]

If you want you could try and see if the top stone could scratch the bottom stone. If they are both corundum there should not be a mark, but if its a softer stone like zircon or spinel there should be mark left.

 

[Heatho]

If you want you could try and see if the top stone could scratch the bottom stone. If they are both corundum there should not be a mark, but if its a softer stone like zircon or spinel there should be mark left.

I'm pretty sure 2 sapphires will scratch each other Shivan, in the rough you can store them all together but after cutting I'd be very carefull about not letting them rub on each other, just what I've heard anyway.

I hate scratch tests, way too subjective. My fav is specific gravity, with good scales it's pretty easy to do and generally will give you a good idea of what's what. Just my opinion of course.

 

[shivan]

You are right a sapphire can scratch another, hardness can vary depending on accessory minerals, but a lot more force would be required to leave a permanent scratch, rather than just crumble a piece of the stone ( I have no idea if the cut edges on a gemstone change this, I have only done tests on rough stones). Where as a light scratch would not mark the sapphire but would a zircon or spinel.

 

[shivan]

You are also right about the test being subjective, that's why when trying to identify a mineral you really need to look at a lot of different things. S.G like you said, hardness, cleavage or fracture, crystallographic shape, streak, colour and clarity etc.

Some tests are just easier to do than others, most struggle to set up a S.G test for the first time.

 

[Heatho]

You are also right about the test being subjective, that's why when trying to identify a mineral you really need to look at a lot of different things. S.G like you said, hardness, cleavage or fracture, crystallographic shape, streak, colour and clarity etc.

Some tests are just easier to do than others, most struggle to set up a S.G test for the first time.

Yeah your spot on with that info too mate. I've seen a hell of a lot of sapphires over the last few years and not all of them have all of the attributes on each stone, sometimes it's the conchoidal cleavage that will distinguish them, sometimes it's the hexagonal crystal structure or the colour. Sometimes they have a few attributes and sometimes your left scratching your head too until an SG test is done, lol.

One thing though is great quality gemstones are instantly recognisable as soon as you hold them up toward the sun and get a good show of transparency and colour, it's actually the bomby ones that can be difficult to recognise.

I'm hanging to get out and find some more, hopefully in a few weeks I'll be heading North for a dig.