1:45 PM - 3:15 PM
[O08-P32] Observation on oxide film of Bismuth hopper crystals by using Rock Guard method
Keywords:Bismuth hopper crystals, Oxide film, Retardation
Bismuth is a metallic mineral that forms characteristic crystals called hopper crystals and various structural colors.Seniors conducted experiments on the size and color of bismuth hopper crystals using a low melting point alloy mixed with cooling means and lead, and announced it.They took over their experiments and investigated the structural color.From the experiment, it was confirmed that the structural color was an oxide film, and the oxide film was sliced and observed with a polarizing microscope.However, since the oxide film is quickly scraped off by the usual method of making, the flakes were made by surrounding and protecting them with rocks. It was named the ROCK-GUARD method because it is guarded by rocks.With this method, the thickness of the flakes can be estimated from the interference color of the minerals in the rock without thinning to 0.02 to 0.03 mm, and the characteristics of the oxide film can be investigated from the retardation of the oxide film.