About Us

About Keystone Granite

Keystone Granite is based on a rock solid foundation, a marriage. Owners John and Lynn Monahan have, for the past 25 years, worked with the residential and commercial markets doing a combination of solid surface, natural, recycled, and engineered countertops. 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 countertop and stone industry in San Antonio and the surrounding areas.

“For years they have portrayed exactly what a family owned business should be. They pride themselves on their work ethic, their experience and their commitment to quality work. They are striving to become the fabricator of choice among San Antonio builders.”

The culture of Keystone Granite is friendly and engaging which leads to competitive pricing, prompt turnarounds, consistent top quality workmanship, and friendly helpful customer service. We realize that everything is on a timetable when building a new home. We have developed a system that let’s us promise some of the most efficient service in town to builder’s and their customers.

“Keystone sets itself apart from the competition with its follow through, experience, and ability to foster client relationships.”

Working with suppliers, locally and overseas, we are able to provide a very large and very diverse slab inventory. On a given day, the slab inventory at Keystone Granite will contain 100 to 200 different colors and upwards of 1000 physical slabs. We are an importer, a distributor, a fabricator, and an installer. We do it all and we try to pass those cost savings on to every one of our customers.