Demantoid thoughts?

[Hivona]

Demantoid has been on my gemstone wishlist for over a year now. I love green and want to add one to my collection! Here are a few screen shots from a video of a 1.59ct Namibian demantoid. I didn’t ask about heat treatments. Should I care about that with demantoids? Seller said it’s $800 per carat. Is that reasonable? It’s definitely less than Yvonne Raley’s demantoid price per carat but I think most of her demantoids are Russian and smaller. Thank you in advance for any insight, thoughts, and opinions!

 

[Stone Hunter]

I would want to see more photos of this stone. It looks a bit dark for my personal taste but then has reflections that look much lighter. Perhaps they used very strong lighting? Could they take a photo outside in shade for you?

 

[MakingTheGrade]

Nambian material tends to be much cheaper than russian, in part because they are more "grass" with the yellow/brown undertones compared to the spectral green or slightly blue undertone of the russian ones.

They are still really pretty in their own right though if like the color! The dispersion is still a show!

 

[minousbijoux]

If it matters to you, I'd ask for a video taken in artificial light, including fluorescent. This is because Namibians are notorious for being gorgeous green in bright daylight, but definitely showing more olive-y green coloration at other times. It still has great scintillation and sparks of color, just more olive-y in nature.

That said, it looks to be a lovely stone, and I have no regrets of getting my Namibian demantoid!

 

[T L]

Namibians are shifty, and can be a very pretty bluish green in some lighting, while turning more brownish green (olive) in others. I would ask for photos in artificial vs natural light. Nice cutting though and I bet it’s very dispersive. Reminds me if a green diamond, just in the soft side (mohs of a 6).

 

[T L]

Duh, I basically repeated what Minous said. Lol

 

[Hivona]

Thank you for the responses. I’m still going to think on it. Not sure I want to bother the vendor for more photos/video if I’m not seriously considering purchasing. I have been keeping an eye out for demantoid but hadn’t found the one. When I saw this one I was feeling wow!!! It’s from a PS trusted vendor but I’ve read that vendor might a little more costly than others. This gem is kind of expensive for my gem budget & wasn’t sure if it was a good price or a great stone & I should jump on it or not. Im also saving for a silvery/platinum/grey sapphire so I might just stick with that for now... can’t buy them all as much as we might want to!

 

[arglthesheep]

Yes as written above, mostly namibian demantoids are not that good coloured so normally much cheaper then the russian ones. But russian can also come in not good colours (if you focus on the intense green ones). the less yellow the better is the colour normally. There are many sources for demantoid at the moment in the market. We see many good coloured stones from iran also in the market which can rival very good russian stones as well.
But you have to have in mind, that very good coloured demantoids can demand 2000/ct and more. To my knowledge russian demantoids are only heated from one source out of the 3 well known ones.
here is one short article:
https://gsa.confex.com/gsa/2017AM/webprogram/Paper294617.html

 

[Anne111]

Isn't it the high dispersion that makes demantoids so much more expensive than other garnets? By that measure most colors, unless ugly by personal tastes, should be fine. BTW, those horsetail feathers (never seen them), do they not decrease luster? I vote Namibian.

 

[T L]

Top quality demantoid is a very saturated green color with lots of dispersion. Horsetails can be microscopic, but they shouldn’t be so numerous, they impede the sparkle. The best colored demantoids come from the Urals, and they can also be very dispersive. It is exceedingly rare to find a rich green with lots of dispersion, especially in a size over a carat, but they do exist. Namibians are still lovely, it’s just the color shift that can bother some people. Demantoid also come from Iran as well I think, don’t quote me on that. I believe those have horsetails as well.

 

[Stone Hunter]

Top quality demantoid is a very saturated green color with lots of dispersion. Horsetails can be microscopic, but they shouldn’t be so numerous, they impede the sparkle. The best colored demantoids come from the Urals, and they can also be very dispersive. It is exceedingly rare to find a rich green with lots of dispersion, especially in a size over a carat, but they do exist. Namibians are still lovely, it’s just the color shift that can bother some people. Demantoid also come from Iran as well I think, don’t quote me on that. I believe those have horsetails as well.

Are you saying that Demantoid Garnets have MORE dispersion than other garnets? I don't even know how to accurately look this up so I just want to clarify what you said above. Thanks.

ETA: I'm sick this week and am obviously confused. According to GemSelect both RI and Dispersion are higher in Demantoid than Spessertite. Very interesting.

 

[T L]

Are you saying that Demantoid Garnets have MORE dispersion than other garnets? I don't even know how to accurately look this up so I just want to clarify what you said above. Thanks.

ETA: I'm sick this week and am obviously confused. According to GemSelect both RI and Dispersion are higher in Demantoid than Spessertite. Very interesting.

Yes, they do have more dispersion, and a higher refractive index than all other garnets. When cut in a diamond round, a very popular cut since I believe they have a similar crystal shape to diamond, they can look like green diamonds, especially when small. I have several small melee size demantoids that I would love to set in a halo to a pink gem. They give off flashes of the rainbow, and are quite lovely. However if color is more important to you, then a nice tsavorite will do, but they don’t give off fire. As I said before, it’s difficult to find larger deep green demantoid, most therefore appreciate them for their fire and dispersion.

I would also avoid cloudy material or those with huge horsetail inclusions, as they impede this refractive property. Namibians tend to be cleaner than Russian material imo. That’s what’s nice about them.

One more thing to note is that they’re a bit softer than other garnets, so use caution when setting them.

 

[T L]

Sphene is another pretty greenish gem that looks a lot like demantoid, but it’s very soft at a 5, and it is doubly refractive. Demantoid has single refraction. Both stones are very refractive, but sphene is easier to find in large multi carat sizes. It also comes in a brownish yellow color.

 

[arglthesheep]

Namibians are still lovely, it’s just the color shift that can bother some people. Demantoid also come from Iran as well I think, don’t quote me on that. I believe those have horsetails as well.

yes the iranian, italian and also the canadian demantoids do have horsetails as well as it is characteristic of a serpentinite geographic origin.
As asked above yes the horsetail do diminish the dispersion as it is normal for inclusions, but some are really great to look at.

 

[Hivona]

The Gem Trader has a demantoid with a neat horsetail. It looks super cool on the macro shots but overall I’m not loving the stone and the price is more than I am comfortable spending so it still sits on his website.

 

[Stone Hunter]

Yes, they do have more dispersion, and a higher refractive index than all other garnets. When cut in a diamond round, a very popular cut since I believe they have a similar crystal shape to diamond, they can look like green diamonds, especially when small. I have several small melee size demantoids that I would love to set in a halo to a pink gem. They give off flashes of the rainbow, and are quite lovely. However if color is more important to you, then a nice tsavorite will do, but they don’t give off fire. As I said before, it’s difficult to find larger deep green demantoid, most therefore appreciate them for their fire and dispersion.

I would also avoid cloudy material or those with huge horsetail inclusions, as they impede this refractive property. Namibians tend to be cleaner than Russian material imo. That’s what’s nice about them.

One more thing to note is that they’re a bit softer than other garnets, so use caution when setting them.

THANKS for all these details. I actually like the color of the Russian Demantoids I've seen listed by Yvonne Raley on Etsy.

@Hivona may have a different color preference than me or want her stone to be larger. Hopefully she can find the perfect stone soon!

 

[MakingTheGrade]

I’ve wanted to get a demantoid but I find I like the clear crystal of a spectral tsav more. Or if I want that strong geeen silky glow I go towards emerald.
I just haven’t yet seen a demantoid that moves me to buy it yet, especially given the cost. Maybe some day!

 

[leslie1956]

I’ve wanted to get a demantoid but I find I like the clear crystal of a spectral tsav more. Or if I want that strong geeen silky glow I go towards emerald.
I just haven’t yet seen a demantoid that moves me to buy it yet, especially given the cost. Maybe some day!

I like demantoid in the melee sizes, it worked beautifully in an eternity ring and as an accent for an opal pendant. However, I don't like it well enough to justify the price of bigger stones! Tsavorite is probably my favorite green gem followed by emerald.

 

[Hivona]

@Stone Hunter I have favorited a number of Yvonne's demantoids but just haven't made a purchase yet. Always end up spending my money elsewhere! Eventually, I will want to get a Russian with a horse tail for my collection "just because"... and a demantoid from some other locale just because... I love green gems, it might be my favorite gemstone color. I have a tsavorite that I am very happy with so that box has been checked for now! Emerald and demantoid are still blank!

 

[Stone Hunter]

@Stone Hunter I have favorited a number of Yvonne's demantoids but just haven't made a purchase yet. Always end up spending my money elsewhere! Eventually, I will want to get a Russian with a horse tail for my collection "just because"... and a demantoid from some other locale just because... I love green gems, it might be my favorite gemstone color. I have a tsavorite that I am very happy with so that box has been checked for now! Emerald and demantoid are still blank!

Sounds like you have a very well defined list! Keep us updated with your future purchases.