Logo for California Slate

California Slate Company, Inc.

3344 Market Street
San Francisco, CA 94114
+1 (415) 864-6862 Work
+1 (415) 814-2667 Fax
+1 (415) 710-9956 Cell
Globes and Quarry Image

Gray Green (Semi-Weathering) Slate

Sample of Gray Green (Semi-Weathering) Dry, MediumSample of Gray Green (Semi-Weathering) Dry, Close
Sample of Gray Green (Semi-Weathering) Dry, Simulated Roof
Sample of Gray Green (Semi-Weathering) Wet, MediumSample of Gray Green (Semi-Weathering) Wet, Close
Sample of Gray Green (Semi-Weathering) Wet, Simulated Roof

Gray Green (Semi-Weathering) Slate Solar Reflectance Index Logo

Gray Green (Semi-Weathering) Slate is the quintessential Vermont slate. Quarried since the middle of the 19th century, it defines the industry in Vermont more than any other. The tones vary from medium grey to light green. It is of medium-smooth texture and is available in a large number of sizes and weights.

Gray Green (Semi-Weathering) Slate is very strong and durable, with a lifespan of over 100 years. It is very easy to install.

When newly quarried it is gray/green, as pictured. When exposed to the elements over time a certain percentage of the slates (perhaps 20%-40%) will change color, developing the tones of brown, pink, and buff seen on distinctive roofs throughout the Northeast.

Varying lengths and thickness can be made to order. Meets Solar Reflectance Index (SRI) to qualify as Title 24 Cool Roof Approved.

Technical Details

Size: 18″ × 12″ to 12″ × 8″

Thickness: 14 

Weight: 850 lbs/sq.

Provenance: Vermont

  • SRI Testing Certificate: