Gem Hut - Tanzanite (Zoisite) Gemstones

Tanzanite (Zoisite) Gemstones

Hardness

6.5 on the Mohs scale.
Occurrence

Zoisite occurs in Tanzania (tanzanite) and Kenya, Norway, Austria, Western Australia, Italy, USA (North Carolina)
Appearance

Tanzanite, colored by Vanadium, is normally heat treated to bring out the intense purple, blue and greyish colors. The color seen depends on the angle they are viewed from. Under incandescent lighting, they can appear more violet. Can be confused with iolite. Tanzanite is also produced synthetically, and a new treatment of beryl produces a dark blue beryl that is very similar in color to tanzanite.
Enhancements

Tanzanite is usually heat treated to produce violet-blue color.

More information on gemstone enhancements.
Gemstone Family

Tanzanite is a member of the Zoisite gemstone family.
Heat Treatment

Violet-Blue Tanzanite is the result of heat-treatment, as the following photo illustrates:

Tanzanite

Tanzanite	$ 40.00/pr
TNZ190	0.40 ct. total, 'A' Grade
	2.8mm Round Cut
	Light
	Moderately Strong Violetish Blue
	Very Slightly Included
	[H] Heated to improve color.
	Only one pair available.

Tanzanite	$ 134.99/pr
TNZ192	0.24 ct. total, 'A' Grade
	3.0mm Round Cut
	Light
	Strong Bluish Violet
	Loupe Clean
	[H] Heated to improve color.
	Only one pair available.

Tanzanite	$ 59.99
TNZ195	0.33 ct., 'A' Grade
	4.0mm Round Cut
	Light
	Strong Bluish Violet
	Loupe Clean
	[H] Heated to improve color.
	Quantity Available: 2

Tanzanite	$ 174.99
TNZ206	0.34 ct., 'AAA' Grade
	4.3mm Round Cut
	Medium
	Moderately Strong Bluish Purple
	Loupe Clean
	[H] Heated to improve color.
	One of a kind.

Tanzanite	$ 3,304.99
TNZ111	4.11 ct.
	14.0x7.9mm Pear Cut
	Medium Dark
	Strong Bluish Violet
	Flawless
	[E] Routinely enhanced.
	One of a kind.

Bi-Color	$ 889.99
TNZ181	1.80 ct.
	9.0x6.7mm Pear Cut
	Medium
	Vivid Violet
	Loupe Clean
	[E] Routinely enhanced.
	One of a kind.
With Greenish Yellow.

Tanzanite	$ 49.99
TNZ106	0.39 ct.
	6.9x3.0mm Marquise Cut
	Medium
	Strong Violetish Blue
	Slightly Included
	[E] Routinely enhanced.
	One of a kind.

Calibrated Tanzanite

Specify size, shape and quality when ordering. Prices are subject to change without notice. Actual carat weight may vary from the average carat weight listed.

AAA Clean, medium dark bluish purple, brilliant, excellent cut and polish, no color zoning.
AA Clean, medium dark, bluish purple, good cut, good polish, good brilliance, little or no color zoning.
A Clean, medium light, bluish purple, good cut, good polish, good brilliance, little or no color zoning.
B Clean, light, bluish purple, good cut, good polish, good brilliance, little color zoning.

Tanzanite		Quality	AAA	AA	A	B
Shape	Size	Avg. Weight	Price Each
Round Cut	1.75mm	0.03 ct.		$ 10	$ 7
	2mm	0.04 ct.		$ 10	$ 8
	2.25mm	0.06 ct.		$ 13	$ 11
	2.5mm	0.08 ct.		$ 17	$ 14
	2.75mm	0.10 ct.		$ 22	$ 15
	3mm	0.12 ct.		$ 26	$ 21
	3.5mm	0.19 ct.		$ 42	$ 34
	4mm	0.27 ct.	$ 104	$ 74	$ 53
	4.5mm	0.42 ct.	$ 166	$ 135	$ 84
	5mm	0.55 ct.	$ 262	$ 169	$ 128
	5.5mm	0.70 ct.	$ 441	$ 286	$ 168
	6mm	0.88 ct.	$ 681	$ 606	$ 382
	6.5mm	1.15 ct.	$ 1,046	$ 890
	7mm	1.40 ct.		$ 1,262

			AAA	AA	A	B
Oval Cut	4x3mm	0.20 ct.	$ 48	$ 34	$ 26
	5x3mm	0.25 ct.	$ 62	$ 45	$ 35
	5x4mm	0.37 ct.	$ 95	$ 78	$ 54
	6x4mm	0.50 ct.	$ 209	$ 130	$ 89
	7x5mm	0.85 ct.	$ 405	$ 268	$ 174
	8x6mm	1.35 ct.	$ 861	$ 574	$ 367

			AAA	AA	A	B
Pear Cut	4x3mm	0.16 ct.		$ 28	$ 19
	5x3mm	0.23 ct.		$ 46	$ 32
	6x4mm	0.45 ct.		$ 136	$ 81
	7x5mm	~		$ 169	$ 162
	8x6mm	~		$ 237
	9x6mm	~		$ 339
	10x7mm	~		$ 509

			AAA	AA	A	B
Marquise Cut	4x2mm	0.09 ct.	$ 22	$ 16	$ 11
	5x2.5mm	0.15 ct.	$ 44	$ 31	$ 23
	6x3mm	0.25 ct.	$ 78	$ 62	$ 42
	7x3.5mm	0.38 ct.	$ 127	$ 97	$ 80
	8x4mm	0.60 ct.	$ 235	$ 194	$ 141
	9x4.5mm	0.85 ct.	$ 441	$ 333	$ 260
	10x5mm	1.15 ct.	$ 704	$ 499

			AAA	AA	A	B
Emerald Cut	4x3mm	0.20 ct.	$ 82	$ 64	$ 44	$ 24
	5x3mm	0.27 ct.	$ 128	$ 107	$ 95	$ 45
	6x4mm	0.60 ct.	$ 337	$ 286	$ 209
	7x5mm	1.00 ct.	$ 782	$ 612	$ 391
	8x6mm	1.70 ct.	$ 1,720	$ 1,257	$ 882

			AAA	AA	A	B
Trillion Cut	3mm	0.10 ct.		$ 22	$ 16
	3.5mm	0.16 ct.		$ 44	$ 37	$ 31
	4mm	0.23 ct.	$ 89	$ 62	$ 53	$ 44
	4.5mm	0.31 ct.	$ 125	$ 89	$ 72	$ 64
	5mm	0.45 ct.	$ 188	$ 155	$ 108	$ 89
	5.5mm	0.55 ct.	$ 337	$ 234	$ 128
	6mm	0.75 ct.	$ 491	$ 389	$ 204
	6.5mm	0.88 ct.	$ 621	$ 509	$ 284

			AAA	AA	A	B
Straight Baguette Cut	4x2mm	0.13 ct.		$ 33	$ 25
Straight Baguette Cut	5x2mm	0.17 ct.			$ 41

			AAA	AA	A	B
Princess Cut	2mm	0.06 ct.		$ 15	$ 11	$ 10
	2.25mm	0.07 ct.		$ 19	$ 12	$ 10
	2.5mm	0.09 ct.		$ 23	$ 15	$ 13
	2.75mm	0.11 ct.		$ 27	$ 20	$ 17
	3mm	0.15 ct.		$ 57	$ 43	$ 31
	3.5mm	0.24 ct.		$ 98	$ 66	$ 48
	4mm	0.35 ct.	$ 176	$ 142	$ 102
	4.5mm	0.45 ct.	$ 291	$ 195	$ 136
	5mm	0.58 ct.	$ 498	$ 405	$ 296
	5.5mm	0.85 ct.	$ 838	$ 614	$ 434
	6mm	1.10 ct.		$ 814	$ 561

			AAA	AA	A	B
Cabochon, Round Cut	4mm	~			$ 15
	6mm	~			$ 47
	8mm	~			$ 89
	10mm	~			$ 187

Tanzanite (Zoisite) Gemstones

Hardness

Occurrence

Appearance

Enhancements

Gemstone Family

Heat Treatment