Production manner null of high purity platinum for ornament and high purity platinum for ornament

摘要

PURPOSE: To produce high purity platinum ('pure platinum') for accessories such as a finger ring practically having sufficient haredness and capable of acquiring a whole mark 'Pt1000'. ;CONSTITUTION: This high purity platinum contains, by weight, ≥99.7% platinum and ≤0.3% boron. The contents of boron are preferably regulated to 0.0001 to 0.25%, more preferably to 0.0025 to 0.2%, and furthermore preferably to 0.0025 to 0.05%. The same high purity platinum is obtd. by subjecting the ingot of a platinum alloy contg. 0.0001 to 0.3% boron to heat treatment in a nonoxidizing atmosphere. The high purity platinum has hardness equal to or higher than that of the conventional 'Pt900', has an effect that the acquisition of the sanction of 'Pt1000' is made possible and has extremely high value as high purity platinum for accessories replacing the sanctified product.;COPYRIGHT: (C)1995,JPO