I knew a girl who had crab nebula once... stayed far away from her. This is great Arthur! I can't wait to see what you bring to BW this year. Your stuff is always inspiring, despite my bad puns. ~ Chris.
For my 6th pointillist mosaic I used transparent 1x1 plates on top of a layer of colored plates. Atop those two layers is a third layer of 1x2 clear transparent plates. This triple layering allows for an amazing number of shades.
All the transparent pieces make it difficult to photograph. I hope to add more photos with time