Pieces Of Eight

Designed Stewart Coffin; left Interlocking Puzzles 2005, right Coffin circa 1980.
(left: mahogany, eight pieces, 3.25 inches,
right: mahogany, walnut, szjo, eight pieces, 2.75 inches;
right is one of 6 puzzles purchased during a visit with the designer in the early 1980's)

Featured in a December 1991 article in Fine Woodworking Magazine. Described in Stewart Coffin's book The Puzzling World of Polyhedral Dissections; here is some of what he says in the directions that came with the puzzle:
"Special version - only one made. No half-pieces, so ignore puzzle problems that require half-pieces. The cube has only one solution in which all sides have matched wood and grain symmetry."
The pieces are the eight ways to glue together a basic U-shaped piece; below are the pieces of the Interlocking puzzle version, the one made by Stewart Coffin pulled apart, and his grain pattern:

The wood and grain restriction has only one solution, but on the other hand, you are given clues how to do it. For example, there is just enough walnut to go around (a total of 8 squares), and so the solution cannot have any of the walnut squares hidden in the middle. For the single wood version, here is one of the solutions:

Interlocking Puzzles Solution
For the single wood version, Interlocking Puzzles said that there are 7 solutions each with a symmetric version; here is the solution sheet that was sold with the puzzle: