They are VERY easy to make. They are the backs of plain dominos. I then use rubber stamps (a couple of these are from Tim Holtz) and stamped the images in Stayz On permanent ink brown. Then I rubbed the sides in the same brown color ink to finish them. I haven't decided if they will become magnets or if I should frame it as a set.
All about alcohol inks! This page has color charts, combinations, a collection of techniques and projects. Including using alcohol ink with polymer clay, metal leafing, domino art, mixing with glues and other mediums to tint them for glazing, glass paint, faux enamel, miniature food syrups and beverages, etc.