When a Florida client commits to slate, three quarry origins typically come up: Vermont (specifically the Slate Valley region straddling the Vermont-New York line), North Country in upstate New York, and Buckingham in central Virginia. They are different stones, and they perform and read differently on a roof.
Vermont (Slate Valley)
The American slate that most people picture. Cooler grays, deep purples, and a distinctive grayish-green ("unfading green"). The quarries here are over a hundred fifty years old; the stone is consistent and well-characterized.
- Hardness: Mohs 3.5-4
- Absorption: very low (<0.25%)
- Color stability: high — "unfading" varieties hold for the life of the roof
- Cost: roughly $14-18 per square foot for raw tile, before fabrication, freight, and install
- Best on: Mediterranean Revival, Tudor, Shingle Style, Craftsman
North Country
Quarried in Granville, New York, just across the state line from the Vermont fields. The geology is similar but the stone runs slightly different — North Country reds and unfading purples are more saturated than Vermont's. Smaller production volume; lead times can run longer.
- Hardness: Mohs 3.5-4
- Absorption: very low
- Color stability: high
- Cost: comparable to Vermont, slightly higher on saturated colors
- Best on: homes where a specific color match drives the specification
Buckingham (Virginia)
A different stone entirely. Black slate, denser and harder than Vermont or North Country. Quarried since the 1700s. The Buckingham stone is the choice when the architecture wants pure black slate — not very dark gray, not blue-black, but actual black.
- Hardness: Mohs 4-4.5
- Absorption: lowest of the three (<0.20%)
- Color stability: extremely high — Buckingham does not change appreciably over a century
- Cost: typically 20-30% higher than Vermont equivalents
- Best on: Federalist, Georgian Revival, formal estate work
Which we specify when
For most Florida Mediterranean Revival work: Vermont unfading green or unfading gray-black. The traditional choice; widely available; matches the architectural language.
For estate work where the architect has specified a color that Vermont cannot quite hit: North Country.
For Federalist or formal Georgian Revival: Buckingham, almost always.
What we will not specify
Imported slate from regions with less established quality control — primarily certain Asian and South American sources. The stone may be cheaper at delivery; the field performance over twenty years has not been good. Slate is a hundred-year material; the savings on the front end do not justify the risk on the back.
A note on freight
All three quarries are northeastern. Freight to Florida runs $1.50 to $3.50 per square foot depending on the route and the season. Plan accordingly; the freight is not a small line item on a 4,000-square-foot project.
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