Samples of each material in the flag are removed for examination. All samples are microscopically analyzed for caparison with known samples to identify the materials used in the flags construction.
Colored samples are processed to extract the dyes from the yarns using heat, solvent solutions and varying the Ph. The dyes extracted from the yarns are analyzed using High Pressure Liquid Chromatography (HPLC) and a Photodiode Array (PDA) detector. The HPLC unit runs at 2500psi. and has 4 solvents and solutions of chemicals to separate the mixtures of dyes and identify them individually when they are retained in a 15cm Supelco C18 column.
Spectrum results generated from the PDA are matched with dye standards certified by Dr. Helmut Schweppe, a career dye analyst for BASF, Germany. These dye standards are the same used by the Smithsonian Institute in Washinton, DC, and the J. Paul Getty Institute in Malibu Beach, Los Angeles, CA, and are the same dye samples Fonda Thomsen used when she was doing this type of work.
I had no interest in getting involved in the authentication of textiles, but when Fonda retired it was imperative that someone with the capability and integrity to take it over did so, in order to keep the market from being flooded with fakes. It is merely my desire to aid in the preservation of history. When someone can do it better, I will gleefully hand it over to them.
Best regards to all
Shannon Pritchard
www.oldsouthantiques.com