Quartz in brecciated rock.

Quartz in brecciated rock.

Bryn Y Rafr mine, West Wales. Common in Hydrothermal ore deposits, brecciated rock is produced by means of hydraulic brecciation. The walls of host rock within fissures is fractured because of changing pressures in hot circulating mineral rich fluids, and is mixed with minerals precipitating from the fluids as it cools,In this instance Quartz.