Chloritic Breccia

Metamorphic rock carved by water into tinajas in the Rincon Mountains

NPS Photo

Breccia (BREH-chi-a) is a hard rock made of cemented-together fragments of other rocks. Chloritic breccia (klor-IT-ick BREH-chi-a) contains the mineral chlorite and is the name given to a type of beautiful, greenish-blue metamorphic rock that is typically found along streams in the Rincons. This rock forms distinctive bands and is often carved into smooth, elaborate shapes by eons of rushing water and sand. Since the chlorite forms a cement material, the breccia is less fractured than other surrounding rocks, which allows groundwater to pool above it in tinajas and springs.