In this journal article, staff at the Boston Museum of Fine Arts report on the use of glass bristle brushes for the conservation cleaning of metallic yarns and ornaments from old textiles. Solid and wrapped threads and ornaments in solid and covered silver and/or gold were used. Examination showed signs of wear and gilt loss as well as surface dirt and tarnish. Known methods of chemical cleaning were rejected for three reasons: 1) yarns of natural fibers harmed by chemicals; 2) difficulty of isolating support materials and 3) problems of rinsing large or complex items to remove or neutralize residual chemicals. Methods for using glass bristle brushes are described and photo illustrated. Advantages, limitations and precautions are discussed. The subsequent application of dilute polyvinyl acetate (PVA) as a preservative to delay oxidation did not alter the appearance of yarns but did make them stiffer. Reference is made to a Russian method for cleaning using a rubber eraser, presumably with similar limitations plus problems associated with contact between metal of sulphur compounds.