The photo specimen is an example of a native Alaskan Ulu, hand made, probably from an old sawmill blade. It has seen at least 50 years of service.
Fancier versions can be ordered from various sources in Alaska, and from some knife vendors. These vendors also sell a concave chopping block to go with them - but I have it on very expert authority this is not authentic - they're aimed at the tourist market. In their natural environment these knives are used against either a flat slab of wood or against a hide, depending on what is being cut. Photo © William Oxley, used by permission.
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