Answer: The rock described, containing flattened pieces of pumice and small crystals of quartz and feldspar, is most likely a type of volcanic rock called rhyolite. Rhyolite is an igneous rock that forms from the rapid cooling and solidification of magma or lava. It is characterized by its fine-grained texture and can contain various minerals, including quartz and feldspar. The presence of flattened pieces of pumice, which is a type of volcanic glass, further supports the identification of the rock as rhyolite. Rhyolite is commonly found in volcanic regions and can exhibit different colors depending on the mineral composition present.
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