Microinch

Mean

Average

Grade Number

and

Grit Size

Spectrum

Diamond Compound Color

Group A

Finest Select Work

.3

.000

# 1/4 (0 - 1/2 micron)

Ivory

.5

.00

# 1/2 (0 - 1 micron)

Grey

1

.0

# 1 (0 - 2 micron)

White

2

.2

# 3 (2 - 4 micron)

Violet

Group B

For General Purpose

High Polish Mirror

Finishes

3

.4

# 6 (4 - 8 micron)

Indigo

3 - 4

.5

#9 (8 - 12 micron)

Dark Blue

4 - 5

.5 - .75

# 15 (12 - 22 micron)

Light Blue

Group C

For Fast Stock Removal

6 - 8

1 - 1.5

# 30 (22 - 36 micron)

Green

10 - 15

2 - 3

# 45 (36 - 54 micron)

Yellow

20 - 25

3 - 4

# 60 (54 - 80 micron)

Tan

Group D

For Heavy Stock Removal

30 - 35

5 - 6

# 90 (170 Mesh)

Orange

35 - 40

8 - 10

# 120 (120 Mesh)

Red

40 - 45

12 - 16

# 150 (100 Mesh)

Black