Fitting structure of rectangular parallelopipedal blocks

A rectangular parallelopipedal block for fitting with substantially identical blocks, said block comprising:

• six rectangular exterior surfaces defining three pairs of opposed rectangular surfaces, each of said surfaces has a length and a width which is less than said length;
• and
• a pattern of concavities and convexities formed on each of said six rectangular surfaces of said block,
• each of said patterns of concavities and convexities has a symmetry of rotation of at least every 180 degrees around the center of said rectangular surface, respectively, and a complementary symmetry of axis with respect to a center line passing through the center and being parallel with a side of said respective rectangular surface,
• wherein said patterns of concavities and convexities of each pair of rectangles are congruent.

A plurality of interfitting rectangular parallelopipedal blocks, each said block comprising:

• six exterior rectangular surfaces defining three pairs of opposed rectangular surfaces;
• a pattern of concavities and convexities formed on each surface of said three pairs of opposed rectangular surfaces,
• each of said patterns of concavities and convexities has a symmetry of rotation at least at every 180 degrees around the center of said rectangular surface, respectively, and a complementary symmetry of axis with respect to a center line passing through the center and being parallel with a side of said respective rectangular surface,
• wherein each said pattern of concavities and convexities of at least one of said pairs of opposed rectangular surfaces has a symmetry of rotation at every 90 degrees around the center of said respective rectangle, and said patterns of concavities and convexities of each said pair of surfaces are congruent so that when the length and the width of one of said plurality of blocks are aligned with the length and the width of another one of said plurality blocks, said blocks can be interfit without regard to the radial orientation of said blocks.

A plurality of interfitting rectangular parallelopipedal blocks, each said block comprising:

• six exterior rectangular surfaces defining three pairs of opposed rectangular surfaces, each of said surfaces has a length and a width which is less than said length;
• a pattern of concavities and convexities formed on each surface of said three pairs of opposed rectangular surfaces,
• each of said patterns of concavities and convexities has a symmetry of rotation at least at every 180 degrees around the center of said rectangular surface, respectively, and a complementary symmetry of axis with respect to a center line passing through the center and being parallel with a side of said respective rectangular surface,
• wherein said patterns of concavities and convexities of each said pair of surfaces are congruent so that when the length and the width of one of said plurality of blocks are aligned with the length and the width of another one of said plurality of blocks, said blocks can be interfit without regard to the radial orientation of said blocks.