All Birchwood patinas are considered traditional patinas that will age or darken metal. These patinas are sold concentrated and should be diluted with distilled water (up to 50%) before use. A clear sealer should be applied when completed to protect the finish and avoid rust. PC-9 Black is a spray, brush, or immersion patina for Iron & Steel. These patina solutions come concentrated and are then diluted with distilled water. Normal dilution ratios would be 1:1, 2:1 or 3:1 (patina to distilled water). Using the solution too strong may cause problems.
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