The half square triangle unit is probably the most commonly used patch in a quilt block -- well it is second only to the square. It is made simply with two triangles, filling up half the square each -- hence the name. Take a quick look through this website, or in any quilting magazine, and you will start to notice that this half square triangle, regardless of its size, is present in more quilts than not.
Free Quilt Block Pattern
The Sandy Dunes quilt block is an easy block using only squares and (my favourite) flying geese units. The block is sewn as an uneven nine patch, rather than in five rows, even though it is a five patch block. (This is my preference, but you can certainly sew it in rows if you like.)
I played around with the block when making the sample quilt illustrations. As you can see, one is set on point and the other is a simple straight set with sashing. By changing up the sashing colours there is a visual secondary pattern forming a sort of "staircase" effect. Then adding extra blank blocks to the quilt on point gives a different geometric look to that quilt. What can you come up with?
More Sun and Surf blocks
~ By the Sea
~ Lady of the Lake
~ Little Boat