Spessartite & hessonite... whats the difference?

[innerkitten]

Just curious. I noticed the topic about garnets below and it made me wonder since the two can be pretty close in color.
Thanks.

 

[cflutist]

IK, what would you like to know?

Hessonite - yellow-orange to reddish orange grossularite, chemical composition Ca3Al2(SiO4)3

Spressartite - yellowish orange to reddish orange, chemical composition Mn3AL2(SiO4)3

Both Singly Refractive

Refractive Index: H=1.740 (+.020/-.010) S=1.810 (+.004/-.020)

Dispersion: H=.028 S=.027

Specific Gravity: H=3.61 (+.12, -.04) S=4.15 (+.05/-.03)

Cause of Color: H=iron S=manganese and some iron

Hardness: both 7 to 7.5

Toughness: both fair to good

Cleaning Methods:
Ultrasonic: Both=usually safe: risky if contains liquid inclusions

Steamer: Both=never

Warm Soapy Water: Both=safe

Stability:
Reaction to Heat: Both=abrupt temperature changes likely to cause fracturing
Stability to Light: Both=stable
Reaction to Chemicals: H=slightly attacked by hydrofluoric acid S=very slowly attacked by hydrofluoric acid

 

[movie zombie]

InnerKitten, good to see you''re still posting!

personally, i find the hess to be more golden and often times a golden brown. spess is more orange. both can be in the red tones. if you see them together, you can definitely tell which is which.

movie zombie

 

[portoar]

Ok, now, what is the difference between Mandarine and Spessartite? Is Mandarine just a color type of Spessartite, or it''s own variety of garnet? I am so confused about this.

 

[Richard Sherwood]

Spessartite tends to be a brighter and more pure color than Hessonite, due to it's main coloring agent of magnesium versus the main coloring agent of iron for Hessonite.

Iron always subdues the intensity of a hue with either a brownish or grayish mask. Warm colors such as red and orange are subdued with a brown mask, while cool colors such as blue or green are subdued with a gray mask.

That's why a Burma, Kashmir or Sri Lankan sapphire "light in iron" will usually appear more vivid than a Thai or Australian sapphire "heavy in iron". The same goes for Hessonite (heavy in iron) verus Spessartite (lighter in iron).

Portoar, there are four categories of Spessartite:

1. Spessartite, from sources other than that listed below
2. Spessartite-Mandarin, from Namibia, Africa
3. Spessartite-Nigerian, from Nigeria, Africa
4. Spessartite-Kashmirine, from the Pakistan side of Kashmir

Spessartite-Mandarin usually has the most pure hue of orange, and consequently is usually the most expensive.

 

[movie zombie]

Date: 5/12/2006 12:06:04 AM
Author: Richard Sherwood
Spessartite tends to be a brighter and more pure color than Hessonite, due to it''s main coloring agent of magnesium versus the main coloring agent of iron for Hessonite.

Iron always subdues the intensity of a hue with either a brownish or grayish mask. Warm colors such as red and orange are subdued with a brown mask, while cool colors such as blue or green are subdued with a gray mask.

That''s why a Burma, Kashmir or Sri Lankan sapphire ''light in iron'' will usually appear more vivid than a Thai or Australian sapphire ''heavy in iron''. The same goes for Hessonite (heavy in iron) verus Spessartite (lighter in iron).

Portoar, there are four categories of Spessartite:

1. Spessartite, from sources other than that listed below
2. Spessartite-Mandarin, from Namibia, Africa
3. Spessartite-Nigerian, from Nigeria, Africa
4. Spessartite-Kashmirine, from the Pakistan side of Kashmir

Spessartite-Mandarin usually has the most pure hue of orange, and consequently is usually the most expensive.

and most beautiful, imo!

movie zombie

 

[portoar]

Thanks for clarifying -- so if it''s from Namibia, it''s Mandarin? I have never seen one of these (or indeed any spessartite garnet) in person and would love to.

 

[innerkitten]

Hi Movie Zombie, I''m still around sometimes
Thanks for posting that info.

 

[movie zombie]

richard''s info was indeed informative and specific.

hope to hear from you again soon, Inner Kitten!

movie zombie