scope:

1.1 This specification covers the determination of muscovite mica splittings of standard commercial grades and specifies the maximum allowable physical defects for each grade. It is applicable to commercially available natural muscovite mica splittings regardless of the basic color of the mica or its source.

1.2 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.

1.3 This standard is very similar to ISO 6386. It is expected that materials would be classified identically using the criteria of either standard. The grades shown under "ASTM Grade No." in Table 1 and Table 2 are shown under "Old Grade No." in ISO 6386-1981.

(A) 1 in.² = 6.45 cm² .(B) 1 in. = 25.4 mm (exact).(C) Minimum and maximum thickness of a single splitting in the case of bookform splittings shall be agreed upon between the purchaser and the seller.(D) Upon agreement between the buyer and the seller, the minimum area may be 1¹/₂ in.² (9.7 cm ²). (A) Not to be included with total allowable defects.(B) Lots that contain more than 2 % of stained splittings in which the sum of the major dimensions of the stains exceed ¹/₄ in. (6.4 mm) shall not be regarded as meeting these standards. No mineral stain shall be permitted in Bookform Splittings. No more than 30 % of the stain in Nos. 4, 5, and 5¹/₂ Loose with Powder shall be mineral stain. No more than 40 % of the stain in Nos. 6 Loose with Powder, 6-1st, 6-2nd, and 6-3rd Loose, shall be mineral stain.(C) To include an evaluation of undersize splittings for other defects.(D) Examine for the defect listed.(E) No hole shall be permitted.(F) Count as a defect if more than 20 % of the periphery is rough or burred.(G) Same as Footnote^F except 35 %.(H) Do not examine for the defect listed.(I) Determine undersize in accordance with Table 1.

abstract: