Irregular building units having mating sides

1. An irregularly-shaped building unit comprising:

a front surface;

a rear surface opposite of the front surface;

an outer contour surface extending from the front surface to the rear surface, said outer contour surface being irregularly shaped in the planes of the front and rear surfaces;

a plurality of mating sides disposed on the outer contour surface, wherein at least two mating sides intersect with a major axis, and at least two mating sides intersect with a minor axis, wherein the major axis and the minor axis are generally perpendicular to each other intersecting at substantially the center of the unit, wherein the dimension of the unit along the major axis is longer than the dimension of the unit along the minor axis, wherein each of the plurality of mating sides is a centered rotation about the respective axis that the mating side intersects with, and wherein each of the mating sides has substantially the same configuration such that each mating side of one building unit can mate with any mating side of a second building unit.

2. The building unit of claim 1 , wherein the at least two mating sides that intersect with the major axis each define lines that are generally perpendicular to the major axis, and the at least two mating sides that intersect with the minor axis each define lines that are generally perpendicular to the minor axis.

3. The building unit of claim 1 , wherein the mating sides are spaced apart from one another, and wherein the outer contour surface further comprises a plurality of non-mating corner portions, each corner portion extending from a first mating side that intersects with the major axis, to a second mating side that intersects with the minor axis, wherein the corner portions are configured not to mate with other said units.

4. The building unit as in claim 3 wherein at least one of said corner portions has a configuration that is different from at least one other of said corner portions.

5. The building unit of claim 1 wherein each of the mating sides is bisected by one of the major axis and the minor axis to form a first segment on one side of the respective axis, and a second segment on a second side of the respective axis.

6. The building unit of claim 5 wherein the first segment is a rotational image of the second segment, wherein the first segment is rotationally spaced from the second segment by an angle of about 180-degrees.

7. The building unit of claim 6 wherein the first segment is subdivided into two sub-segments, wherein the two sub-segments are angled with respect to each other.

8. The building unit of claim 1 wherein the mating sides have a general “S”-curve shape.

9. The building unit of claim 1 wherein each of the mating sides comprises one of a series of straight-line segments, curved segments, and a combination of straight-line and curved segments, at least one of the segments being angled relative to an adjacent segment such that the general appearance of each mating side is irregular.

10. An irregularly-shaped building unit comprising:

a major axis of the building unit;

a minor axis of the building unit intersecting the major axis, wherein the major axis and the minor axis are generally perpendicular to each other intersecting at substantially the center of the unit, wherein the dimension of the unit along the major axis is longer than the dimension of the unit along the minor axis;

a front surface of the building unit;

an outer contour surface extending generally perpendicularly from the front surface, said outer contour surface being irregularly shaped in the plane of the front surface;

the outer contour surface comprising a plurality of mating sides, wherein at least two mating sides intersect with the major axis, and at least two mating sides intersect with the minor axis, wherein each of the plurality of mating sides is a centered rotation about the respective axis that the mating side intersects with, and wherein each of the mating sides has substantially the same configuration; and

the outer contour surface further comprising a plurality of non-mating corner portions extending between each said mating side such that mating sides and corner portions alternate, wherein said corner portions are rounded and irregularly shaped;

wherein each of the mating sides are configured to mate with any mating sides of other of said units.

11. The building unit of claim 10 further comprising at least four said non-mating corner portions around the contour surface, and wherein at least one of said corner portions has a configuration that is different from at least one other of said corner portions.

12. The building unit of claim 10 wherein each of the mating sides comprises one of a series of straight-line segments, curved segments, and a combination of straight-line and curved segments, at least one of the segments being angled relative to an adjacent segment such that the general appearance of each mating side is irregular.

13. An irregularly-shaped building unit comprising:

a front surface;

a rear surface opposite of the front surface;

an outer contour surface extending from the front surface to the rear surface, said outer contour surface being irregularly shaped in the planes of the front and rear surfaces;

a plurality of mating sides disposed on the outer contour surface, each mating side spaced apart from the other mating sides, wherein at least two mating sides intersect with a major axis, and at least two mating sides intersect with a minor axis, wherein the dimension of the unit along the major axis is longer than the dimension of the unit along the minor axis, wherein each of the plurality of mating sides is a centered rotation about the respective axis that the mating side intersects with, and wherein each of the mating sides has substantially the same configuration such that each mating side of one building unit can mate with any mating side of another building unit; and

a plurality of non-mating corner portions disposed on the outer contour surface, each corner portion extending between two mating sides.