Keystone Granite owners John and Lynn Monahan have, for the past 25 years, worked with the residential market doing a combination of solid surface countertops and cabinets. Since the late 90's, when they returned to their hometown of San Antonio, their focus has been on providing a combination of elegance and excellence towards the Granite and Quartz Countertop industry in San Antonio and the surronding areas.

The culture of Keystone Granite is friendly and engaging which leads to competitive pricing, prompt turnarounds, consisent top quality worksmanship, and friendly helpful customer service.

This spirit is backed by state-of-the-art machinery. From laser digitizers to CNC machines, we produce countertops that consitently fit right.

In a recent article, Webb and Friends summed up Keystone Granite well when they stated: