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Our transcription: The chemical changes that accompany contact metamorphism, especially of marbles, is seen on this hand-sized sample of a contact. On the left side is an intrusive igneous rock, a tonalite, that came into contact with a limestone. The limestone was heated up, and at the same time it was heated up there were chemical elements that left the intrusive rock into the marble, and then elements that left the marble and went into the intrusive rock. The material leaving the intrusive rock consisted of some iron, aluminum, and silicon, which went to form garnets, the brown material here. Silica continued in further into the marble than the other two elements and resulted in a formation of a layer of the mineral, wollastonite, which is a calcium silicate.
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