Making gem-quality polycrystalline high-pressure minerals (poly-gems) for sound velocity measurements
Abstract
Making high-quality polycrystalline samples of high-pressure phases are important for precise measurements of their elastic properties by ultrasonic pulse-echo, resonance, Brillouin scattering methods. We succeeded to synthesize consolidated polycrystalline diamond with grain sizes of several tens nanometers (Nano-Polycrystalline Diamond = NPD or HIME-Diamond) by direct conversion from graphite in Kawai-type multianvil apparatus, which is ideal for such measurements. We also started to synthesize other polycrystalline high-pressure minerals using corresponding techniques, and now we are able to make highly transparent polycrystalline garnets, for example, with various chemical compositions. Thus synthesized high-quality polycrystalline bodies of high-pressure minerals, named as "poly-gems", should be useful in the measurements of elastic and other physical properties.A sphere of Nano-Polycrystalline Diamond with a diameter of about 7 mm. A transparent Micro-Polycrystalline Almandine with about 3 mm in diameter and 1 mm thick
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2012
- Bibcode:
- 2012AGUFMMR42A..03I
- Keywords:
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- 3630 MINERALOGY AND PETROLOGY / Experimental mineralogy and petrology;
- 3909 MINERAL PHYSICS / Elasticity and anelasticity;
- 3924 MINERAL PHYSICS / High-pressure behavior;
- 3994 MINERAL PHYSICS / Instruments and techniques