Sphene: What are your thoughts?

RevolutionGems · Jan 29, 2008

Greetings all,

My name is Jeff. I am a gem junkie. I have been collecting for about 3 years now..

I was pretty disappointed with the quality of the cuts on most stones I was seeing so I did something about it. I learned to cut. Now all I have to worry about is the quality of the rough material I get. I know the finished product will be beautiful.

So here is my question: I just purchased a parcel of rough sphene from Pakistan. It is really nice material and I am trying to get a feel for what people want and like. What kind of cuts are your favorite? I personally have a thing for cushions, not a big fan of the pear of marquise.

I have been lurking here for a while and I know there are a few true experts andd a great number of junkies like myself. Reading through the forums is both entertaining and educational.

I hope to hear from some of you. I will post some pics of finished stones as soon as I get them cut.

Pandora II · Jan 29, 2008

Ooooh, please do!

I am currently having a sphene obsession, but I haven''t found THE ONE yet.

Cushions are probably my favourite cut. My e-ring is a long cushion tsav.

I''m kind of leaning towards a fat slightly more rectangular than square cushion (if that makes any sense!) for my next rock!

What sort of colours are your rough?

Can''t wait to see the finished pics.

Welcome to PS by the way!

RevolutionGems · Jan 29, 2008

Hi Pandora-

This material is coming from Pakistan so it is the really nice golden-honey color. Great dispersion, beautiful stuff.

I also really like the green material from Madagascar but I havent had much luck in finding good sized rough of that material though I do have some smaller pieces. It doesn''t seem to have as much dispersion as the Pakistan material.

I understand exactly what you are saying on the longer cushions. I actually have a pattern for an interesting cut called Sultans Seat. I haven''t done a stone in it yet but I think it will be quite cool when it is cut.

Pandora II · Jan 29, 2008

I''m undecided about the yellow or the green.

I did find a nice green one, but it was an EC and the dispersion wasn''t that great - while it was a very pretty colour, I really want mega-fire. ( I wrote and checked out extra details with the vendor.

Does your material have the almost multicoloured look with the red and green flashes?

I''ve never seen a Sultan''s Seat - I''m off to google it now!

RevolutionGems · Jan 29, 2008

Oh, yeah. This stuff has fire like you wouldn''t believe. Lots of red green and yellow flash. I think I have one I cut from a earlier parcel I got from him. If I can get a good shot of it I will post it.

The site where you will find the Sultans Seat pattern (third one down in the google search) has lots of really nice patterns. You''ll see.

Look around on the web for some Pakistani Sphene and you will see what I mean about the fire in this material.

strmrdr · Jan 29, 2008

Hi Jeff welcome to PS!
not too play mini-mod but you seem like a nice guy.
Please review the rules and stay away from advertising.
Your OK so far but a lot of threads like this end up there and the person gets banned.
What happens is someone says I want one where can I get one of yours and the cutter posts a link.
That makes the entire thread advertising and the cutter is gone.
that said and why im posting...

What do you mean that some material has more dispersion is there a wide range of RI in sphene?
Can you post more info?

RevolutionGems · Jan 29, 2008

I''m no gemologist, so take what I say for what it is worth.

The general Ri of sphene is about 1.85. Quite high, but that isn''t the kicker. The killer thing on sphene is its dispersion. It is about.051, which, if memory serves, is quite a bit higher than our good friend the diamond. That means that the fire in these stones is nothing short of astounding. Thats the "technical" part.

I don''t know how variable the RI and dispersion are among sources, but I can tell you from my own experience that the material from Pakistan seems to have far more fire than it''s Madagascar counterpart. That being said, it also seems to depend a great deal on the cut. Ec''s and simple cuts like that do not seem to work well in this material. I find they explode in brilliant and barion-style cuts. In this case, seems like more facets is better.

Again, I am no gemologist (though perhaps someday I will pursue that...)Take it for what its worth.

strmrdr · Jan 29, 2008

hmmmm in that case if you have some rough that will cut into a round without too much waste a double RB sounds like a nice challenge :}

strmrdr · Jan 29, 2008

or how about this one:
http://www.rockhounds.com/rockshop/gem_designs/snow3/snow3.html

I love this one
http://www.rockhounds.com/rockshop/gem_designs/hummers1/

this style for an oval
http://www.rockhounds.com/rockshop/gem_designs/christmas_oval_2001/

classic checker
http://www.rockhounds.com/rockshop/gem_designs/checker_square_cushion/

FrekeChild · Jan 29, 2008

I personally like ovals and more round cuts. Just my preference though!

RevolutionGems · Jan 30, 2008

I have a whole bunch of different patterns but, of course, there are a few that I really like.

For rounds, I like one called Park Lane and another called Button. Both are quite good.

For ovals, I have on called the Rainbow Oval that is spectacularly bright and doesn''t display as much extiction as most oval cuts.

I also have a pattern called the Smith Bar that, while simple, I think it would work quite nicely in sphene. It has an EC-like outline (square or rectangular with cut corners) It is an opposed bar cut with lots of activity. I think the activity would more than make up for the limited number of facets in the cut.

I am starting a couple of cuts tonight. I think I am going to try the Smith Bar and see what happens. It takes me two days to cut a stone so look for pics on Friday.

Pandora II · Jan 30, 2008

Hi Jeff,

Can you post a few pics of the rough?

I''ve got a contact whose looking at some of the pakistani sphene at Tucson this next week for me, but I''d love to see some photos of your uncut rocks!

We''re all looking forward to seeing what you cut. It''s so nice to see things that are a bit different and can do wonders for the character of different stones

That''s if you don''t mind.

RevolutionGems · Jan 30, 2008

I''ll take a few shots tonight and post them tomorrow.

A few tips on sphene buying:

Most sphene is included in the form of veils, fractures and needles. However, there is enough clean material on the market that cut stones are expected to be clean or very close to it. However, don''t necessarily shy away from the lightly included material as those inclusions give the cut stone a great deal of personality and an extraordinary amount of extra fire.

Sphene crystals also tend to be very flat. Make sure that any rough you buy has enough depth to cut a good stone.

Pakistani sphene shows a rather curious color change. Under incandescent light it is a beautiful honey gold. If you look at it with an LED flashlight, it is bright green like the Madagascar material.

Sphene rough should not be overly expensive. You should be able to get average rough (some clean, some SI to I) for no mor than $3 a carat.

Just a bit of unsolicited advice. Hope it helps.

Pandora II · Jan 30, 2008

Wow, that is so helpful!

If said that dispersion is No. 1, colour is secondary - I''m not worried about a bit of inclusion. I like personality in my rocks!

Any idea what top quality rough is like price-wise?

I am I right in thinking that ''bigger is better'' with this material?

Sorry for the million and one questions!

I was haunting the gemmology section at the Natural History Museum in London a couple of months ago - which is in a very sorry state. Most of their specimens are really quite poor, but they had this one knockout stone. Yup - their sphene. I was blown away by it. Since which I have been trying to find out what I can.

I know they''re only a 5 on the moh, but how brittle are they? I haven''t managed to find much on cleavage etc

I''m planning a pendant that will be worn once in a blue moon (I''m just going to sit and gaze at in basically

) , so the setting will depend on what problems I''m likely to be coming up against with setting.

RevolutionGems · Jan 30, 2008

Not a problem!

I would say you should probably pay no more than $5 a carat unless your are looking at a giant stone (50+ carats) that is completely clean.Also remember that the avarage yield from a piece of rough is around 20%. Sphene crystals are also almost always twinned (in fact I have never seen on that wasn''t)which means that you may lose a bit more of the rough depending on the depth of the faces between the crystals.

Yes, it is pretty soft (like you said 5 - 5.5) so I would not recommend it for rings or daily wear jewelry but I it does not seem to be overly brittle, though I wouldn''t want to smack it on the desk. Cleavage has never been a problem for me and if it is going to be a problem, it will usually show up during cutting. I suspect that you wouldn''t encounter any problems with a prong set and a careful jeweler. I would be a little hesitant to bezel set it as that requires a bit more muscle and some heart-stopping pounding near the stone.

The "bigger is better" thing is just like most other stones. It is really up to you and what you like. My taste runs toward smaller stones, say, no more than about 3 or 4 carats. Most of the stones I cut are around a carat but that is due in large part to the expense of good cutting material.

In any case, if you can find some good rough and a good cutter, you will surely end up with a spectacular stone that can s hold its own against just about any other stone from a beauty standpoint.