как я перевел с использованием паст перфект

  • Long before cerium found application large reserves of compounds of cerium had been accumulated in form of waste that had been formed during production of salts of torium from the mineral of the monazite.
    Interest in cerium appeared after it had been discovered that alloys of cerium and iron posses the interesting property - had you stroke a piece of such alloy on/against rough steel surface, sparks would appear of the 200°C temperature.

  • THORIUM.

    Ну, что же, все понятно. Я думаю, что с паст перфект проблем тут нет.
    Long before people began to use cerium, large reserves of cerium compounds had been accumulated as waste material obtained in the production of thorium salts from monazite (or a minetal called monazite).
    People took an interest in cerium after it had been discovered that alloys of cerium and iron possesed an interesting property-hardly had a person struck a piece of such an alloy on a rough steel surface when very hot sparks were produced. The temperature of the sparks reached 200°C! (or...when very hot sparks whose temperature reached 200°C were produced).