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California Slate Company, Inc.

3344 Market Street
San Francisco, CA 94114
+1 (888) 994-0842
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Del Castillo Gray Slate

Sample of Del Castillo Gray Dry, MediumSample of Del Castillo Gray Dry, Close
Sample of Del Castillo Gray Dry, Simulated Roof
Sample of Del Castillo Gray Wet, MediumSample of Del Castillo Gray Wet, Close
Sample of Del Castillo Gray Wet, Simulated Roof

Del Castillo Gray Slate Solar Reflectance Index Logo

A California Slate Company exclusive. Truly non-fading and non-weathering, Del Castillo Gray is difficult to find – we are the only U.S. company to carry it. It is a medium gray slate, lightly textured with just a vague hue of silver or blue. Unparalleled durability puts this remarkable slate in a class of its own. It will maintain its original look for generations.

Del Castillo Gray comes from Spain’s oldest operating quarry dating back to the 16th century. The stone is Bernardos phyllite which the International Union of Geological Sciences named as a “Heritage Stone” in 2022. Del Castillo Gray adorns many of the stately buildings throughout Europe and was used in most buildings erected by the Spanish monarchy from the 16th through the 19th centuries.

The test results for Del Castillo are unequalled even by the Vermont slates. This means it can be used in extreme or high alpine conditions. Rated S1 Grade pursuant to ASTM standards. It is consistently easy to work (no power tools needed) and has a 100-year guarantee. Meets Solar Reflectance Index (SRI) to qualify as Title 24 Cool Roof Approved.

  • House built using Del Castillo slate.

Technical Details

Size: 16″ × 10″ and 16″ × 8″

Thickness: 14″ to 38(7 to 9mm)  

Weight: 950 lbs/sq.

Provenance: Spain

  • CE Conforming Declaration: