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rare

frankfort green

iron-furnace slag

frankfort green, illustrated

The tell

Same story as Leland blue, green instead. Glassy, bubbled, and it started life in a furnace.

Frankfort and Elberta in Benzie County. Late 1800s iron furnaces.

What it gets mistaken for

The facts

Put it on the shelf

Every stone on this chart is drawn and kiss-cut at three inches. The rarer the stone, the fewer exist: only 250 frankfort green will ever be printed, then the run is retired.

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