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giovedì 24 maggio 2012

FDA INSPECTIONS AND ANCIENT ALCHEMY FORMULAS

Example of a ceramics artist's worktable 

A technical note about colors and glazes in ceramics making

In the last thirty years shipping majolica from Deruta, Italy to the United States has not been an easy matter as far as large shipments leaving the factories is concerned. Towards the end of the 1970s FDA has started applying very strict rules to producers regarding lead contents (and cadmium contents, which is not mentioned most of the time) in ceramics, so strict that all the colors and glazes had to be changed accordingly. As a little girl I have practiced the art of painting and I noticed that after the change to leadfree powders, colors were sort of watery, thinner and it was much harder to paint as if powders had lost their body. Indeed artists had to go through retraining in the use of the new paints. New colors were also more time-consuming to apply.

Ceramics colors come from tin oxides, powdered metals mixed with water, fired at about 1800° F.
The white background glaze comes from ground sand,  the base of the glass making: silicon

Since the late 1970s to nowadays ceramics factories exporting on a steady base must declare that their glazes and colors were purchased from certified suppliers. This is a very important certification that is necessary to present to the FDA inspectors upon request in case of investigation. If FDA finds lead in the shipments, they do not hesitate to drill holes in all of the ceramics pieces, so that these pieces cannot be of further usage. As a curiosity the official suppliers of ceramics glazes of the past thirty years are the same suppliers of dentists for their best porcelain teeth. Therefore we can be sure we are buying the perfect  healthy products.

This is the reason why when a note came in the mail that there are still artists making their own glazes and colors, I was very surprised and I did not take the trouble to double check if this information could be true. I thought of some romantic description and nostalgic remembrance of alchemy formulas of Renaissance times. My first thought went to FDA and how things had changed for everybody in Deruta. On the contrary the piece of information about selfmade glazes and colors was true and coming from a respected and knowledgeable source.

I was glad to notice that the pieces that these artists make are for decoration only, therefore they are supposed not to be for food use, by adding the description "for decoration only" on the back of the plates before shipment (with a permanent marker is fine, if this description is missing), you might avoid drills on beautiful wall plates,  although inspections by FDA on private shipments are very rare.

It was great to know that in contemporary times there are artists who stick to ancient Renaissance traditions, there is much passion in this choice, passion is what these specialists claim about themselves: searching raw metal materials, collecting ground sand from the rivers, grinding metal stones into powders, mixing powders with the most unimaginable natural sources, weighing, mixing, balancing, fusing and creating magical alchemies with lots of secret recipes and a few secret places where they find their own materials for their artwork.


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The most common metals and metalloids with which colors are made are: manganese (deep purple), copper (green), cobalt (blue), antimony (yellow). 


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- Original Posts by Roberta Niccacci -

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