Carat Size	Round MM	Marquise  MM	Pear MM	Emerald MM	Oval MM	Heart MM	Triangle MM	Approx CZ wt
.005	1.0
.01	1.3
.015	1.5
.02	1.7
.025	1.8
.03	2.0
.035	2.1
.04	2.2
.05	2.4
.06	2.5
.07	2.7
.08	2.8
.09	2.9
.10	3.0	4x2
.11	3.1
.12	3.2
.14	3.3
.15	3.4
.16	3.5
.17	3.6
.18	3.7
.20	3.8		4x2
.22	3.9
.23	4.0
.25	4.1	5x2.5		5x3	5x3	4x4
.30	4.2	6x3	5x3
.33	4.4
.38	4.6	7x3.5
.40	4.8
.47	5.0
.50	5.2	8x4	6x4	6x4	6x4	5x5	4x4x4	.85ct.
.60	5.4
.65	5.6					5.5x5.5
.75	5.8	9x4.5	7x5	6.5x4.5		6x6	5x5x5	1.25ct.
.80	6.0
.95	6.4
1.00	6.5	10x5	8x5	7x5	7x5	6.5x6.5	6x6x6	1.70ct.
1.10	6.6
1.17	6.8
1.25	7.0				7.5x5.5
1.33	7.2
1.50	7.4	11x5.5	9x6	8x6	8x6	7x7	7x7x7	2.55ct.
1.60	7.6
1.75	7.8
1.90	8.0
2.00	8.2	12x6	10x7	8.5x6.5	8.5x6.5	8x8	8x8x8	3.40ct.
2.15	8.4
2.25	8.6
2.50	8.8	13x6.5	12x7	9x7	9x7	8.5x8.5	9x9x9	4.25ct.
2.85	9.2
3.00	9.4	14x7	12x8	10x8	10x8	9x9	10x10x10	5.10ct.
3.15	9.6
3.35	9.8
3.50	10.0	14x7.5	13x8		10x8.5	9.5x9.5		5.95ct.
3.75	10.2
4.00	10.4	16x8	14x8	11x9	11x9	10x10		6.8ct.
4.25	10.6
4.50	10.8		14.5x9		11x9.5		10.5x10.5
5.00	11.2	16x8.5	15x9	12x10	12x10	11x11		8.5ct.

PLATINUM	3224	1773
15%IRIDIUM PLAT.	3310	1821
10% IRIDIUM PLAT.	3250	1788
5% IRIDIUM PLAT.	3235	1779
RHODIUM	3571	1966
24K GOLD	1945	1063
18K YELLOW	1700	927
18K WHITE	1730	943
18K PINK	1655	902
14K YELLOW	1615	879
14K WHITE	1825	996
14K PINK	1715	935
10K YELLOW	1665	907
10K WHITE	1975	1076
10K PINK	1760	960
SILVER, PURE	1761	961
STERLING SILVER	1640	893
COIN SILVER	1615	879

1 gram	15,4324  grains
1 gram	.642 penny weights
1 gram	.03215 troy ounce
1.5517 grams	1 pennyweight
31.1048 grams	1 troy ounce
1000 grams	1 kilogram
1 kilogram	32.15076 troy ounces
1 pennyweight	24 grains
1 pennyweight	.05 troy ounces
20 pennyweight	480 grains
20 pennyweight	1 troy ounce
14.5833 troy ounces	1 pound avoir
12 troy ounces(5760 grains)	1 troy pound
16 avoid ounces(7000 grains)	1 avoid pound
avoir weight x .823	troy weight

Convert From:  To:	Weight Multiplied by Factor
10k to Alloy	Wt. X .77
10k to SS	Wt. X .88
10k to 14k	Wt. X  1.14
10k to 18k	Wt. X 1.30
14k to Alloy	Wt. X .66
14k to SS	Wt. X .77
14k to 10k	Wt. X .88
14k to 18k	Wt. X 1.14
14k to PT	Wt. X 1.75
18k to 10k	Wt. X .77
18k to 14k	Wt. X .88
18k to PT	Wt. X 1.42
PT to 14k	Wt. X .57
PT to 18k	Wt. X .70
SS to Alloy	Wt. X .88
SS to 10k	Wt. X 1.14
SS to 14k	Wt. X 1.30
SS to 18k	Wt. X 1.48
Alloy to SS	Wt. X 1.14
Alloy to 10k	Wt. X 1.30
Alloy to 14k	Wt. X 1.48
Alloy to 18k	Wt. X 1.69
Wax to Brass	Wt. X 8.50
Wax to 14k	Wt. X 14.0

Gemstone	Refractive Index	Specific Gravity	Hardness
Alexandrite	1.746-1.755	3.73	8.5
Amethyst	1.544-1.553	2.66	6.5
Apatite	1.634-1.638	3.18	5
Aquamarine	1.577-1.583	2.67-2.84	7.5 to 8
Black Onyx			6.5 to 7
Black Star Sapphires			9
Bloodstones			6.5 to 7
Blue Lace Agate			6.5 to 7
Blue Sapphires			9
Blue Topaz			8
Cameo (Shell)			3 to 4
Carnelian			6.5 to 7
Catseye			7
Chatham Emeralds			7.5 to 8
Chrysophrase			6.5 to 7
Citrine	1.544-1.553	2.66	7
Coral			3 to 4
Cubic Zirconia	2.15	2.66	8.75
Diamond	2.417	3.52	10
Emerald	1.577-1.583	2.67-2.84	7.5 to 8
Garnet	1.72-1.875	3.30-4.18	6.5 to 7.5
Hematite			5.5 to 6.5
Iolite	1.53-1.55	2.58-2.66	7 to 7.5
Ivory			2 to 3
Jade-Jadeite	1.654-1.667	3.30-3.36	6.5 to 7
Jade-Nephrite	1.60-1.627	2.90-3.02	6 to 6.5
Jasper			6.5 to 7
Kunzite	1.666-1.676	3.18	6 to 7
Lapis Lazuli	1.5	2.40-2.90	5 to 6
Malachite			3.5 to 4
Marcasite			6 to 6.5
Moonstone	1.520-1.525	2.56-2.62	6 to 6.5
Opal	1.45	1.25-2.22	5.5 to 6.5
Pearls-Cultured	1.52-1.66	2.60-2.78	3 to 4
Peridot	1.654-1.690	3.31-3.48	6.5 to 7
Rhodalite			7 to 7.5
Rose Quartz			7
Ruby	1.762-1.770	4.00	9
Sapphire	1.762-1.770	4.00	9
Smokey Quartz			7
Sodalite			5 to 6
Spinel	1.718	3.57-3.90	8
Tanzanite	1.691-1.704	3.30	6.5
Tigereye			7
Topaz	1.619-1.627	3.53	8
Tourmaline	1.624-1.644	3.01-3.21	7 to 7.5
Turquoise	1.61-1.65	2.60-2.80	5.6
Zircon	1.810-1.984	3.93-4.73	6 to 6.5

 

Millimeter To Inch Converter Chart

MM	Approximate Size In Inches	Exact Size In Inches
1mm	1/32 Inch	0.03937 Inches
2mm	1/16 Inch	0.07874 Inches
3mm	3/32 Inch	0.11811 Inches
4mm	1/8 Inch	0.15748 Inches
5mm	3/16 Inch	0.19685 Inches
6mm	Just short of 1/4 Inch	0.23622 Inches
7mm	Little over 1/4 Inch	0.27559 Inches
8mm	5/16 Inch	0.31496 Inches
9mm	Just short of 3/8 Inch	0.35433 Inches
10mm	Little over 3/8 Inch	0.39370 Inches
11mm	7/16 Inch	0.43307 Inches
12mm	Just short of 1/2 Inch	0.47244 Inches
13mm	Little over 1/2 Inch	0.51181 Inches
14mm	9/16 Inch	0.55118 Inches
15mm	Just short of 5/8 Inch	0.59055 Inches
16mm	5/8 Inch	0.62992 Inches
17mm	Just short of 11/16 Inch	0.66929 Inches
18mm	Just short of 3/4 Inch	0.70866 Inches
19mm	Little over 3/4 Inch	0.74803 Inches
20mm	Just short of 13/16 Inch	0.78740 Inches
21mm	Little over 13/16 Inch	0.82677 Inches
22mm	Just short of 7/8 Inch	0.86614 Inches
23mm	Little over 7/8 Inch	0.90551 Inches
24mm	15/16 Inch	0.94488 Inches
25mm	1 Inch	0.98425 Inches