Compliments of
The International Gem Society

American Std.	Micron Size	Equivalent Mesh
1/4	0 - 0.5	100,000
1/2	0 - 1	60,000
1.0	0 - 2	14,000
1.5	1-2	13,000
2.5	2-3	9,000
3	2-4	8,000
4	2-6	5,000
5	4-6	4,500
7	5-10	2,800
9	6-12	1,800
14	8-20	1,400
15	10-20	1,200
18	12-25	1,050
25	20-30	800
30	20-40	600
35	30-40	500
45	40-50	325
55	50-60	285
70	60-80	240
90	80-100	225
110	100-120	160

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