Colored Resin
These are various shapes of resin - rectangles, discs, squares or lozenges - colored with resin colorant. Those that are completely uniform were made by pouring a quantity of colored resin into a mold. The ones that are mottled or variegated were made in some cases with an initial layer of clear resin, left undisturbed until it hardened. Then drops of colored resin were applied, followed by drops of another color and then another, each layer allowed to harden before continuing.
In one case - "Medusa" - colored resin was applied, wet on wet, to fresh clear resin and allowed to bleed naturally into the clear. The drop technique (using an eye dropper) is difficult to control, so many of these are as much the product of chance as they are of planning. I'm usually more of a control freak in my work, but here I've had to embrace unpredictability, bubbles and all. It wasn't what I had in mind, but when I see them enlarged here on the computer screen (much larger than their actual sizes), some remind me of the light shows of the rock concerts of the 1960s and 1970s.