12ct Tourmaline (Cabochon, 17.13×11.42mm, Purple) vs 12ct Quartz (Cabochon, 17.97×11.98mm, Brown)
Quick summary: When looked from above (face-up position), 12ct Quartz (17.97×11.98mm, cabochon cut) appears 10% larger than 12ct Tourmaline (17.13×11.42mm, cabochon cut). See below how they compare side-by-side on a ring and finger.
| 12ct Tourmaline (cabochon cut) |
vs
|
12ct Quartz (cabochon cut) |
|
purple |
|
|
| 17.13×11.42 mm | 17.97×11.98 mm | |
| actual size | ||
|
|
|
Actual size is set for screen
|
Ring:
Skin tone:
Ring width: 3.0 mm
|
|
64 mm |
|
|
|||||||||||||||||
|
|||||||||||||||||||||
Actual sizes of
12ct Tourmaline Cabochon (17.13×11.42mm, Purple)
and
12ct Quartz Cabochon (17.97×11.98mm, Brown)
as they would appear on a ring and finger.
Adjust the ring and finger size to get an idea of how these gemstones would look on your finger.
Where to buy?
For certified gemstones, high-end gemstone jewelry, and birthstone jewelry, see Blue Nile
Face-up Size
All things being equal, Tourmaline will face-up smaller than Quartz for a given
carat weight, because it has higher specific gravity
(3.06 vs. 2.65 - this means it's "heavier" compared to Quartz of the same size). Face-up size also depends heavily on the proportions of the cut.
Face-up area is a measure of the size of the gem when viewed from above (as set in a ring). It tells you how big the gem is at the girdle plane.
Face-up area is a measure of the size of the gem when viewed from above (as set in a ring). It tells you how big the gem is at the girdle plane.
| 12 Ct Tourmaline (Cabochon) | 12 Ct Quartz (Cabochon) | |
| 17.13×11.42 mm | vs | 17.97×11.98 mm |
| 160.41 mm² | 176.53 mm² |
| 12ct Tourmaline Cabochon (17.13×11.42mm) | |
| 12ct Quartz Cabochon (17.97×11.98mm) | |
| Difference: 10% (16.12 mm²) |
12ct Quartz (Cabochon, 17.97×11.98mm) has approx. 10% more face-up area than 12ct Tourmaline (Cabochon, 17.13×11.42mm).
Popular comparisons:
- 1.2ct Tourmaline (Cabochon, Violet, 7.92 x 5.28) vs. 0.45ct Sapphire (Pear, Blue, 6.36 x 3.83)
- 4ct Tourmaline (Cabochon, Violet, 11.82 x 7.88) vs. 5ct Emerald (Cabochon, Green, 13.34 x 8.89)
- 1ct Tourmaline (Cabochon, Dark Bluish Green, 7.46 x 4.97) vs. 1ct Hiddenite (Cabochon, Green, 7.38 x 4.92)
- 1ct Tourmaline (Cabochon, Violet, 7.46 x 4.97) vs. 1ct Emerald (Emerald, Green, 7.28 x 5.39)
- 22ct Tourmaline (Cabochon, Purple, 20.97 x 13.98) vs. 22ct Quartz (Cabochon, Brown, 21.99 x 14.66)
- 3.87ct Tourmaline (Cabochon, Violet, 11.7 x 7.8) vs. 2.87ct Tourmaline (Oval, Violet, 11.7 x 7.8)
- 4.98ct Tourmaline (Cabochon, Violet, 12.72 x 8.48) vs. 4.13ct Tourmaline (Cabochon, Violet, 11.96 x 7.97)
- 4.98ct Tourmaline (Cabochon, Violet, 12.72 x 8.48) vs. 4.13ct Ruby (Cabochon, Red, 10.98 x 7.32)
- 2.85ct Tourmaline (Cabochon, Violet, 10.56 x 7.04) vs. 1ct Emerald (Emerald, Green, 7.28 x 5.39)