四国産オリビンサンドの特質

抄録

  Structural observation on dunite and some characteristics of olivine sand made from this raw ore produced from small scale Imono rocks found among the Higashi Akaishi ultra basic rock zone in Shikoku Island of Japan were studied. This dunite is surpentinized considerably and the ignition loss is approximately 6%. It contains small amount of chromite, magnetite, brucite, spinel and pyroxene. The grain shape is angular and goes up to a maximum value of 1.5 in terms of grain shape number. Endothermic reactions occurring at peak temperatures of about 400, 660 and 760°C and the exothermic reaction at 800°C peak temperature were observed. After 30minutes calcination at 900°C in air, the endothermic and exothermic reactions vanish and the ignition loss falls to less than 0.2%.