A true ‘quartzite’ is composed almost entirely of recrystallized, interlocking quartz grains. During metamorphism, a protolith quartz-rich sandstone is subjected to heat and pressure by geologic ...

"And other stable grains like quartz cannot be dated because they lack radioactive elements that can give us an age. "There are undoubtedly super-old quartz grains in the Jack Hills samples ...

They submerged quartz crystals in a gold-rich fluid and ... Remarkably, the gold had a tendency to deposit on existing gold grains rather than forming new ones.” The electric spark generated ...