Twelve Points To Insanity

Purchased from Mr. Puzzle Australia 2006, level 1, no holes.
(six wood pieces, 3.5 inches)

Mr. Puzzle Australia credits this puzzle as being sold as early as 1875, and as having been sold under a number of names, including the Cluster, the Gem Cut Puzzle, the Chestnut Burr, and the Snowflake. When assembled it looks like a standard version of the Simple Six Piece Burr (where pieces have a diamond cross section). However, it actually is composed of six identical pieces where two assemblies of three slide together.