What is "flake knife"

Flake \Flake\ (fl[=a]k), n. [Cf. Icel. flakna to flake off, split, flagna to flake off, Sw. flaga flaw, flake, flake plate, Dan. flage snowflake. Cf. Flag a flat stone.]

1. A loose filmy mass or a thin chiplike layer of anything; a film; flock; lamina; layer; scale; as, a flake of snow, tallow, or fish. ``Lottle flakes of scurf.''
   --Addison.

   Great flakes of ice encompassing our boat.
   --Evelyn.

2. A little particle of lighted or incandescent matter, darted from a fire; a flash.

   With flakes of ruddy fire.
   --Somerville.

3. (Bot.) A sort of carnation with only two colors in the flower, the petals having large stripes.

4. a person who behaves strangely; a flaky[2] person. Flake knife (Arch[ae]ol.), a cutting instrument used by savage tribes, made of a flake or chip of hard stone. --Tylor. Flake stand, the cooling tub or vessel of a still worm. --Knight. Flake white. (Paint.)

   1. The purest white lead, in the form of flakes or scales.

   2. The trisnitrate of bismuth.
      --Ure.