BS680 certificate of slate test report of Westone black slate

--- Westone black slate comply with BS680 part 2 1971

Acid immersion test of black slate

None of the test specimens showed signs of delamination, swelling, softening or flaking of the surface nor of gaseous evolution during immersion and therefore comply with BS680 part 2 1971 clause 6.2.3

Certificate of test for the acid immersion

Wetting and drying test of black slate

None of the test specimens showed signs of delamination or splitting along the edge nor of flaking of the surface and therefore comply with BS680 part 2 1971 clause 6.2.2

Certificate of test for the wetting and drying

Water absorption test of black slate

The water absorption is 0.3% and therefore complies with BS680 part 2 1971 clause 6.2.1

Certificate of test for determination of water absorption