These are enamel powders - washed and set out to dry. Using the coffee filters for this process makes them look like treats, but enamel is NOT safe to eat. It is however, a treat to work with, and truly "eye-candy" in finished form. This time last weekend, I was finishing the second of two enameling workshops. Students had the opportunity to spend a day becoming more comfortable enameling on silver. They washed, wet-packed, and fired many samples, then enameled a metal clay piece. It was loads of fun and everyone left feeling more confident in their ability to try enameling on their own. This picture shows some of the washed colors left over from the workshop - drying for later use (note: after taking the photo I covered them to prevent contamination while they dried).
Enameling seems daunting to many people - and understandably so. If not done properly, it has the potential for disappointing results. But by following some simple rules and taking the time to practice, your results should be beautiful.
Rule #1 - The rule of "clean." Your metal, your workspace, your hands, tools and enamels must be clean. This means no dust/dirt, metal filings, metal clay, oils, etc., should come in contact with enamel.
Rule #2 - Test colors before using them on a final piece. Pay attention to the firing and don't over-fire. If using Thompson Enamels, The Thompson Enamel Workbook contains a wealth of useful technical information about the enamels.
Rule #3 - Record your results - for example, if you test two layered colors - make a note. Don't leave anything to memory.
Rule #4 - When in doubt, counter enamel. If you're not sure whether your piece needs this support, err on the side of caution.
Of course, this isn't all you need to know about enameling and you can most certainly expect a learning curve. Nothing takes the place of experience. Be patient and your efforts will pay off. And be sure to familiarize yourself with safety considerations in both handling and firing enamels (never ingest enamel).
One of my favorite books on enameling is by Linda Darty. It's called The Art of Enameling: Techniques, Projects, Inspiration.
If you're interested in enameling on metal clay, I wrote a little book that provides an introduction to the process. It's called The Little Book of Water Etching and Enameling for Metal Clay. It contains instructions for water etching and enameling - two techniques that go well together. Here are images of metal clay pieces that are water etched and enameled: