15.60 Ct Pear Diaspore     VS     13.90 Ct Emerald Kyanite



15.60 Carat
21.89 x 13.20 mm



13.90 Carat
15.78 x 11.68 mm
Stone Type
Diaspore Kyanite
Stone Shape
Pear Emerald
Stone Weight
15.60 carat 13.90 carat
Length X Width
21.89 x 13.20 mm 15.78 x 11.68 mm
Length / Width Ratio
1.66 1.35
Approx Face-up Area
210.75 mm² 171.49 mm²
Approx Volume
917.56 mm³ 755.44 mm³
Diaspore Kyanite
Chemical Formula
AlO(OH) Al2SiO5
Crystal Structure
Orthorhombic Triclinic
6.5 - 7 4.5-7
Specific Gravity
3.4 3.68
Gram weight
3.120 gm 2.780 gm
Ounces weight
0.1101 ounces 0.0981 ounces
Refractive Index
1.70 - 1.75 1.710 - 1.735
1,2;2,1 Perfect
Vitreous Vitreous,Pearly
0.048 0.012 - 0.033
Good Very good
Diaspore is not an official birthstone for any month Kyanite is not an official birthstone for any month

Diamond Guidelines 4Cs and More

Before purchasing a diamond, one should make sure it looks its weight. It's important to understand that carat weight does not equal face-up size.

Two diamonds of exactly the same weight (and shape) can vary quite considerably in face-up size. This depends on the proportions of the cut (e.g., deep cuts will face up smaller)..

Face-up area is a measure of the size of the diamond when viewed from the top view.

It tells you how big the diamond is at the girdle plane. It's important for a diamond to have sufficient face-up size for its carat weight

Diamond prices vary greatly as they depend on the combination of unique characteristics (4Cs - Cut, Color, Clarity, and Carat). For best value, it's important to choose the combination that will reduce the price without having a negative impact on appearance.

You also need to consider some of the following points as well

  • Strong blue fluorescence.
  • Fair or Poor symmetry.
  • Extremely thin or extremely thick girdle.
  • Inclusions visible to the naked eye.
  • Diamond Certification.

Blue fluorescence can have a positive, negative, or zero effect on a diamond. Diamonds in the lower color range (H or lower) can benefit from it, as it can make them look whiter, more colorless. On the other hand, strong fluorescence can cause a stone (especially in the higher color range D-G) to appear hazy or milky under certain light conditions. One of the biggest benefits of fluorescent diamonds is that they generally cost less.

Blue fluorescence can be found in 35% of naturally mined diamonds and it makes the stone glow under UV light. Outside of UV lighting environments, there are no visual differences between fluorescent and non-fluorescent diamonds.

However, there exists a big difference in pricing between these diamonds. In the industry, diamonds with fluorescence are usually traded at a 10-15% discount and can go as high as 25% for higher colored diamonds.

GIA grades fluorescence as None, Faint, Medium, Strong, and Very Strong.

There are Many Laboratory Available which provides certification for Gemstones.

  • GIA - Gemological Institute of America
  • AGS - American Gemological Society
  • HRD - The Hoge Raad voor Diamant
  • IGI - International Gemological Institute
  • EGL - European Gemological Laboratories
  • GSI - Gemological Science International

*Different certification labs give different results

Piecut Diamonds are set of small Diamonds, which are cut & polished with Precised Measurements to look like a Single Solitaire diamond which can save 80% to 85% from Solitaire Single Piece Price.

Shapes of Pie Cut Diamonds.

  • 9 Pcs Emerald
  • 9 Pcs Round
  • 4 Pcs Round
  • 3 Pcs Heart
  • 4 Pcs Oval
  • 4 Pcs Pear
  • 4 Pcs Marquise
  • 5 Pcs Star

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