Verneuil process CHMO:0002159 flame fusion A method for preparing synthetic gemstones. A finely powdered sample is melted in an hydrogen-oxygen flame (2000 °C) and crystallising the melted droplets on a boule (a single crystal). https://orcid.org/0000-0001-5985-7429 2009-07-13T01:37:26Z crystal growth method