I can't be the only one to have ever seen this head-scratcher?  Been searching for over a year now, and have found absolutely nothing about it; no other image matching this one found on www as of yet, and no one else who's ever seen it.  I'm not quite sure even what it is supposed to represent/be?  Looking for shape of diamond only turns up lots of diamond marks with number or letter in each of 4 corners that identified the piece, manufacturer, pattern, and such.  Also kind of looks like a H K, or H R in side the diamond, but I've turned nothing up there either.

(fingers crossed) I'm hoping someone here might be able to shed some light on this mystery mark of mine.