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Roman Cement, LLC is a US-based research and development company that has tested and patented binary and ternary blends of Portland cement and supplementary materials, many of them unwanted waste streams from industrial processes.  Roman Cement blends reduce the carbon footprint of cement by 50% to 70% without affecting performance.


As mentioned in National Review, p. 13 (July 15, 2013 issue): 
















"Horace said that his poetry was a monument more lasting than bronze, but if he had been bolder, he might have compared his work to Roman cement.  From a breakwater build in 37 B.C. near Naples and, mirabile dictu, still sturdy, U.S. and Italian researchers have identified how the structure has been able to withstand more than 2,000 years of saltwater pounding against its surface.  The Romans mixed volcanic ash with lime, which absorbed water and reacted with the ash to form the highly stable material we now call pozzolan cement, after Pozzuoli Bay in southern Italy.  Pozzolan cement is stronger than Portland cement, the industry standard in modern construction, and the manufacture of it emits less carbon dioxide, so there’s something in pozzolan cement for environmentalists as well as for architects and engineers, whose ancient forerunners once again show the way."

The Pantheon in Rome, built in ca. 126 A.D.

The binary and ternary blends developed by Roman Cement, LLC are, of course, not  “ancient Roman cement”, because they contain modern hydraulic cement, such as Portland cement.  Nevertheless, such blends seek to emulate the beneficial properties of ancient Roman cement by utilizing substantial amounts of pozzolanic materials.

Roman Cement was jointly invented by John Guynn (B.A., M.S. Chemistry, JD) and Andrew Hansen (B.S. Chemistry, JD) through an intense, ongoing collaboration that has included testing and rigorous validation by the National Institute of Standards and Technology (NIST). They are chemists and patent attorneys with decades of combined technical and legal experience. They invented Roman Cement to satisfy a market need for a hydraulic cement with a lesser carbon footprint and fill glaring gaps in technology and intellectual property that persist due to conservative thinking and market inertia. Because the inventors are patent lawyers, the inventive process and development of IP have been closely intertwined from the beginning.

John Guynn, Co-founder and CEO

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