Low-Blank Crucible for Argon Extraction from Minerals at Temperatures up to 1550°C

The new version of a double-vacuum crucible for fusion of small samples of refractory minerals has been described recently by Halas (2006). This novel type of high temperature crucible was further improved in the following important points: (1) The expensive material, tantalum, was replaced by much cheaper molybdenum which also appears to be significantly less corrosive in the presence of hot boron nitride ceramic used as the insulator, and (2) a versatile temperature controller was assembled from commercially available components.