Extremely Unusual Mt. Washington 3 piece Cup/Saucer Set Brilliant Cut Glass

I have never seen another set like this - it features a handled cup, an underplate and an interior liner than is also cut in pattern. It's truly amazing because the cut design on all 3 pieces can be lined up seamlessly so that it's difficult to see that there are separate pieces. The underplate has an engraved Monogram that looks like a "D" to me. All cut early in the period by Mt. Washington in blockdiamond.
Condition Report: Perfect condition - 6" wide, 3" tall