I guess it's about time I contributed to this forum instead of just lurking and commenting on all of your great mosaic projects. And since I'm way to lazy you'll only get pictures not how tos.
This is my mirror. I finished it hmmm, maybe two years ago after taking a looooong time. I got all the glass blobs and tile on pretty quickly. But then came the grouting. I had some grout left over from a tile job I did so used it. It was fine til I realized one of the two boxes of grout was older and a different batch number. Important to know if you want the colors to match.
Mine didn't. Same color, different batch # = panic!! I discovered this after I used up the first box and while mixing up the second box. I started spreading box two on only to discover it didn't match!! I frantically starting removing the grout from the first batch before it solidified. No easy feat I tell you! I was mostly successful but there were spots here and there where the grout stuck and I pulled off tiles along with it. GRRRR
Lesson learned--but I was so mad I put the whole (blankity blank blank) thing in a spot out of sight (meaning behind the couch, no one ever looks behind the couch ever).
Two years passed before my mosaicy mojo decided to come back. But once it did I went out and bought a BIG tub of grout insuring that I would have enough of the same color to finish my mirror and that I would never run out (at least for this project).
So here it is. Measures about 18" across and weighs a ton. But it's done and I like it.