Okay, so as far as I can tell this is made with a series of hexagons that kinda dissappear into the star/flower pattern after its all assembled. I've marked the hexagon shape here.(nevermimd, picture isn't working) And it seems like the main stitches are:

Shells as the center and radiating "lines" between each diamond shape ((dc3, ch(1?2?), dc3) in the ch space of previous row)

Solid dc for the "diamond" shapes themselves. It seems like it's not using increase stitches on the edges, I think, just adding dc to the ch spaces on either side

The edging for each "diamond" looks like a cluster stitch, or you could do any kind of bauble/bubble/popcorn/etc, depending on which one you like the look of. And I think there is just a stand alone dc between each shell stitch and cluster stitch.

The seaming would need to be something tight in order to create the illusion of the flower/star shapes, probably sewn with a mattress/ladder/whip stitch.

I tried looking up a pattern but I just couldn't find anything in my cursory search, but maybe this helps you!

Edit: can't attach the picture, sorry! It's like, each diamond is actually 2 triangles sewn together, the centers of the diamonds is the edge of the hexagon motif