Chloritic Breccia

Metamorphic rock in a desert stream. The bedrock surrounding a tinaja has a bluish hue and polished look. The background shows the upstream landscape of bedrock, saguaros, and mountains.
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.

Last updated: April 7, 2021

Park footer

Contact Info

Mailing Address:

3693 S Old Spanish Trail
Tucson, AZ 85730


520 733-5153

Contact Us