Our History

Five Generations Of Natural RockAsphalt©

Some people claim that the story of RockAsphalt© begins in 1885 when the Lathe Carbon Company first mined bitumen outside of Uvalde, Texas. Others argue it wasn’t until the early 1890’s when the city of San Antonio used bituminous Anacacho limestone to pave downtown Crockett Street. Still others say the story only really starts in 1928, when cold-mix-cold-laid asphalt began to be shipped to New York City, Philadelphia, and other northeastern states to compete against natural bitumen materials imported from Trinidad.

But we like to think the history of natural rock asphalt actually begins much earlier — 70 million years ago in fact, if you ask most geologists.

It was then during the late Cretaceous period when diagenetic processes first began to transform carbon sediments into the rock we now call Anacacho limestone. Later when pressure from surrounding rock formations caused migrating hydrocarbons to permeate that porous limestone, the result was a unique bitumen impregnated rock, or what geologists today refer to as “native asphalt” or “natural asphalt.”

Granted, when most people think asphalt, it’s not natural but manufactured asphalt that comes to mind. Why? Well, as demand for paved roads increased sharply after World War II, more and more asphalt material had to be artificially manufactured from distilled crude oil and rock aggregate to keep up.