John Greening is one of the world's foremost pursuers of fabulous designs and solutions of the polyiamond family of shapes—shapes made of joining any number of equilateral triangles by their edges. Kadon makes them up through size 8 (see the Octiamond Ring).

John exceeded that in 2018 with his custom order of the 160 enneiamonds (nine triangles each) and, in 2019, the 448 dekiamonds, where each piece is a different shape of 10 equilateral triangles. And in 2020 John sent us the fabulous assembly of all of those in a Grand construction of concentric rings. John's specialty is forming these monster sets into the most beautiful regular shapes, like the three-petaled nested flower above, and the six-petaled nested star and the nested diamonds below. And below that is John's hourglass construction enclosing a fancy dogbone, received in 2020.

In 2021, John surprised us with the longest, skinniest hexagon we've ever seen, built with just the 24 heptiamonds:

And soon after, John Greening made this fine windmill with three congruent stretched hexagons:

At the end of August 2021, this pair of amazing solutions arrived from John Greening, creating star-shaped symmetry combinations of the heptiamonds and hexiamonds:

Another puzzler sent us this dramatic snowflake pattern built with just the heptiamonds:

Two more heptiamond snowflakes arrived from John Greening in October 2022. He commented, "The jagged edges make life interesting."

 
We'll add more here as we collect them.