When slate is put onto a roof, it is expected to stay there, static and maintenance free for many years. Del Carmen slate, from FA Mitchell and Co , is especially and exclusively quarried from the Del Carmen Quarry in North West Spain to offer customers a top of the range European slate, typically in demand in markets such as Germany or France.

The blue/black coloured class A slate is 100 % natural and does not discolour, de-laminate or crack with continual sun exposure. Extensive and regular testing to British, French, German and Belgium standards, coupled with centuries of experience have established  Del Carmen slates amongst the top roof slates available for homeowners and builders. Del Carmen is graded S1 as per the American ASTM standard which guarantees a life expectancy of at least 75 years.

Many quarries in Spain produce slate that satisfies the conditions of BS 680. However, only a small number can pass the more rigorous French standard, P32/302 Class A test. FA Mitchell and Co Del Carmen slate is free from damaging pyrites and sulphates which can cause premature failure. The longitudinal grain as well as inertness to acids, polluted atmospheres and insect attack have made Del Carmen a sought after slate for replacement of roofs on heritage and historical buildings throughout the UK and Scotland.
 
With proper fixing and detailing Del Carmen slates are suitable for pitches as low as 17 degrees.