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Lefty said:
most gemstone values are subjective, they are only worth what someone will pay.

That's the nub of it right there. My fathers collection contains quite a few sapphires that have been formally appraised by a professional valuer and have the valuation certificates. The valuer has valued some of them at prices that I feel they would have some difficulty selling at, except perhaps to a really serious collector.

The valuer is certainly a highly qualified professional - but they are not the buying public.

If John and Jane Public don't agree with the price then good luck in selling it for that much just because you have a piece of paper that says it's worth that.

True for other than diamonds to varying degrees. By the way, Argyle don't sell their champagne diamonds through the diamond exchange - their diamonds were given a much lower valuation by valuers (I suspect still are) so they decided to sell direct to the public and launched a big and successful advertising campaign to convince the public of their value. I think many a Joe and Mary of the public gets a shock when they try to sell their precious stones.....

Valuers here are less experienced in the main and mostly value for insurance purposes (an exaggerated price) - quite unlike the diamond valuers that I was talking about. The certificates mean very little.
 
A bit more info here on the possible origins of the "sapphires are rarer than diamonds" meme. Looks to be a GIA article

It is safe to conclude that up to and through the
1970s, the market for faceted blue sapphire and ruby was small relative to the quantities in the jewelry
industry today, simply because supplies were
limited primarily to the low percentage of facetable
goods (typically less than 5%) that came from the
mines in salable colors. The introduction of effective
heat-treatment techniques to improve the color
and clarity of previously unsalable material, such as
geuda sapphire from Sri Lanka and dark, silky
blue stones from Australia, greatly increased the
quantities of sapphire available to the market, particularly
in the lower-priced commercial qualities.
A similar situation occurred with ruby in the midto-late
1980s after the Mong Hsu deposit was discovered
(Emmett, 2007). And not only did treatments
greatly increase the proportion of facet-grade
material available, but they also allowed development
of deposits where there was little or no naturally
occurring gem-quality material

Having chased sapphires for around the past 35 years or so, this makes sense to me. They are hard enough to find in the first place and when you do, a great deal of them are simply not of gem quality. However, significant numbers of those that are useless as gems in their natural, untreated state can become clear, attractive stones once heat-treated.

Heat treatment has always been available for as long as I have been involved in them as I recall. However, before the process became perfected and widespread, I can easily imagine just how low the rate of recovery for facetable material would have been overall.

So as they come naturally from the ground, a stone that is too small to cut does not a gem quality stone make, except perhaps in a technical sense - and close examination of such tiny stones under powerful magnification might well show that just because you can see through them at a glance it doesn't necessarily mean they are gem quality. By the same definition we might be able to say that gem-quality zircons are as common as sand because there are beaches made of them, even if they are pin head sized and could never be cut. Likewise, a sapphire that is thick and murky with silk (a common occurrence with them despite their overall scarcity) cannot be any more regarded as gem quality than can an industrial grade diamond. Not until it is heated - but it did not naturally come from the ground that way.

Looks a bit difficult to me to make a definitive assertion that one stone is dramatically rarer than the other in naturally-occurring, untreated gem grade material, especially given that sapphire production is not as thoroughly reported and controlled as diamond production. After all the years I've spent chasing them I don;t think I would describe tiny, transparent sapphires below facetable size as "very common" - otherwise I would have drums full of them simply from hand-mining.

This has been an interesting discussion and I'm glad it was held. But I can see it's heading toward unproductive territory so I will now withdraw from it.
 
I agree. I would not say tiny ones were rare here (often a few in a gold pan) but most streams cannot be mined or prospected. Yes, I enjoyed the discussion and learnt some things.
 
Hear in north east Vic I've seen people find sapphires,diamonds,ruby's Sapphires are not that rare here i have seen a few diamonds and one or two ruby's
 
Anyone know what this is? Big chunk of quartz with something on it that I found a few weeks ago, could it be jasper? Fairly smooth with interesting cleavage.
1524317941_p4211018.jpg
 
Jasper or chert would probably be reasonable terms. Incidentally, we don't call those surfaces cleavage - cleavage consists of parallel, planar surfaces that have a constant angular relationship to each other if in different directions, We call what is in your specimen fracture, and that particular type of fracture we call conchoidal (I think it comes from conch - like the inside of a shell). It is typical of many types of glass when they break.
Cleavage is more like this:
https://www.bing.com/images/search?q=mineral+cleavage+photos&qpvt=mineral+cleavage+photos&FORM=IGRE
 
Thanks goldierocks :Y: for some reason I thought cleavage and fracture were the same thing, I guess because they are both to do with how it breaks. But you're right, they are different.
 
I don't really know Mickomarlin, looks like a big chunk of quartz to me, see what the others say. Nice stone!
Here's a stone with interesting patterns in it that I found where I was getting red/green common opal. So it could be opal of some sort, or maybe something else? Almost looks a bit like those patterns you get in agate?
1525315914_p5021019.jpg
 
Another one- little 6 sided hexagonal prisms, many are broken fragments. Seem to be abundant in this particular area. Been calling them garnets but garnets aren't that shape. Maybe rutile? Or corundum?
1525346846_p5031020.jpg
 
Thanks Heatho :Y: that's what I thought too... but I don't think you can get garnets in that hexagonal prism crystal shape? They're meant to be more like a dodecahedron type shape. That clear one stood out to me too, might be some good ones if I keep looking. Got a bit of dirt to go through that should have more of them in it.
 
I do see what you mean but I still think they are garnet, will be interested to see what you get. Anyway I could be wrong, hopefully Goldierocks has a look at the pic for you. :Y:
 
Some look like garnets. I'm not sure about the hexagonal shaped ones. I am assuming they could be apatite??? Corundum doesn't usually have that 'glow' in this rough state . You can see the glow with garnets for example.

You should test to help us get a better idea eg. scratch test or specific gravity if you really want to lol.

Goldierocks probably will help you further. Good luck! - Jack
 
Hoping for an id on this one please, Found at Eldorado about 40 years ago near a pile of rocks near one of the crossings. It is glass like in appearance and is dense black, it is extremely hard and resists grinding with conventional carborundum grinding wheels, in thicknesses of less than about 0.5mm it is yellow in colour. Ken.
1525435942_0001.jpg
 
Also looks like Obsidian to me, but you saying it is yellowish, it could also be smokey quartz. Smokey quartz is much harder than obsidian and is fairly common to find it near Eldorado in the creek.
 

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