Non-Silver Containing Black Chromates

In my December 2003 column (www.pfonline.com/articles/clinics/1203cl_plate1.html), I answered a question regarding black chromate conversion coatings. Part of the question had to do with the availability of a non-silver containing formulation. At the time I answered the question I was not aware of any commercially available formulations. Since responding to this question, I have learned that a commercial non-silver formulation is available. Electrochemical Products Inc., (262) 786-9330, www.epi.com offers such a product.