Thread: Phosphate Opal
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Old 12-03-2006, 06:46 PM
Hugh Jenkins Hugh Jenkins is offline
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Also be absolutely sure you are oxidizing. If you are gas melting, the flame can often be partially reducing at the core even if there is total combustion in the fire box. A really clean burn is needed for phosphate.
Certain colorants that are bi or tri-valent seem to help in maintaining a little longer stability of the phosphate. Manganese at .1% is great for this and won't effect the color. Copper and chrome additions will create color but also extend the life of phosphate opals in the pot. Otherwise it is necessary to get them out within a day or so.
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