Generally, I purchase a set for one, two, or three stones. The price is so reasonable that if I don't like a few stones, I can experiment on them. I like most of the stones on the two cards on the right, but the stones on bottom row on the center card are pretty much duds. There is very little color in them and they look a bit "dirty" because they have little sparkle. They won't be duds when I am done with them!
Check out the stones on the card on the left. I considered the green, the two deep gold, and the two turquoise stones duds because their color was so washed out. Enter alcohol inks. I flooded the crystalline face of each one, waited a minute for the ink to set, and then dabbed away the excess with a tissue. The process was repeated until I was happy with the color. They were then baked at 225 degrees for half an hour. After they cooled naturally, I soaked them for a few minutes in denatured alcohol where only a bit of the color came off. They were then gently washed in soap and water, rinsed and dried. I can't wait to start making bracelet links with these stones!