Interlocking construction blocks

An interlocking construction block comprising:

• a block body having a top surface, a bottom surface, a first outer face and a second outer face, the first and second outer faces meeting at a 90 degree angle to form a corner of the block body;
• a first head portion on a side of the block body adjacent to the first outer face, the first head portion defining a first lobe-shaped outwardly convex surface and a first inwardly concave surface;
• a first flange having an outer edge at an end of the first outer face that is opposite to the corner of the block body, the first flange being adjacent to the first inwardly concave surface, and extending toward the first head portion and defining an end surface that is perpendicular to the outer edge of the first flange;
• a second head portion on a side of the block body adjacent to the second outer face, the second head portion defining a second lobe-shaped outwardly convex surface and a second inwardly concave surface;
• a second flange having an outer edge at an end of the second outer face that is opposite to the corner of the block body, the second flange being adjacent to the second inwardly concave surface, and extending toward the second head portion and defining an end surface that is perpendicular to the outer edge of the second flange;
• a W-shaped element on an outer surface of the block body between the first lobe-shaped outwardly convex surface and the second lobe-shaped outwardly convex surface, the W-shaped element having:
• a first face parallel to the first outer face of the block body;
• a second face parallel to the second outer face of the block body;
• a third face perpendicular to and adjoining the second face;
• and
• a fourth face perpendicular to and adjoining the first face;
• wherein the third face and the second face of the W-shaped element and the first lobe-shaped outwardly convex surface form a vertically-extending groove on the outer surface of the block body adjacent to the first lobe-shaped outwardly convex surface;
• and
• wherein the fourth face and the first face of the W-shaped element and the second lobe-shaped outwardly convex surface form a vertically-extending groove on the outer surface of the block body adjacent to the second lobe-shaped outwardly convex surface.