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Large Aquamarine rough?
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Author:  africadale [ Wed Nov 12, 2008 3:38 am ]
Post subject:  Large Aquamarine rough?

I am unfamiliar with aquamarine. The properties are similar to glass, so I did not purchase this large rough "stone" as the asking price was rather high.

Picture can be viewed at:
http://www.harepix.com/images/2038802795.jpg

origin: iam told it has come from songea area, Tanzania.
colour: bluish green. yellowish rind one corner.
weight: 189 grams
specific gravity: 2.55 (as measured in volume cylinder- more on the glass side of properties though cylinder graduations not that accurate)
shape: large duck egg size/shape, water worn exterior
clarity: eye clean, appears flawless
lustre: vitrious, very bright interior
hardness: seems resitant to glass scratch test, but is scratched by quartz. This should not occur as aquamarine has a hardness of 7.5-8?
fracture: conchoidal
streak: white
polarised lens: i tried with my polaroid sunglass lens at 90 degrees to eachother and it went dark every 90 degrees.

Any comments are appreciated, and or definative tests I could further do.

Author:  Peter Torraca [ Wed Nov 12, 2008 9:15 am ]
Post subject: 

Nice color -- I can see why this would tempt someone.

Those fractures scream glass to me. The water worn pattern looks very much like the pieces of river beach glass I pick up when wandering the shore with the kids.

I think I would have passed on that one too.

peter

Author:  Barbra Voltaire, FGG [ Wed Nov 12, 2008 10:47 am ]
Post subject: 

A Dichroscope and set of hardness points would be handy (as you could really narrow down the hardness with them)...but it doesn't smell like aqua.

Author:  Tim [ Wed Nov 12, 2008 1:00 pm ]
Post subject: 

All the Songea aqua I've seen lately comes from hard rock mining and isn't waterworn. Eighter fragments or full crystals...

not that this is worth much, there may be some alluvial to be found down hill but that has never reached my eyes yet...

Author:  africadale [ Thu Nov 13, 2008 1:24 am ]
Post subject: 

Thank you for your responses.

Author:  johnddyer [ Thu Nov 13, 2008 11:12 am ]
Post subject: 

Looks a lot like a piece of glass that a friend of ours bought in Zambia.

(It was also misrepresented as aqua but had round bubbles in it.)

Author:  winstone [ Wed Oct 07, 2009 11:42 am ]
Post subject:  Aqua rough can be large

Aqua rough or Beryl can be very large. Do not make the mistake that just because it is large that you or a cutter will get a lot of fine stones from the sample. There was a case before the IRS for a charitable donation of a large piece of rough aquamarine. The donor had placed a cut and finished price on the rough piece. Irs rejected the claim as it only gives credit where there is cut stones, not POSSIBLE CUT STONES. If the price is too good to be true, it often is too good to be true, pass on this item if you can not afford to discover you paid aqua prices for a lump of glass. winstone

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