For dry cast stone, the production process is unique. Most cast stone pieces under 500 pounds are produced on steel turntables. The form is placed on the table, clamped into place and filled with material. The mix is then tamped to a high density with pneumatic hammers commonly called "tamp guns".
Tamping is what gives cast stone its remarkable compressive strength. Unlike normal measurable slump concrete, whose strength can be calculated by various factors such as water/ cement ratio and aggregate characteristics, cast stone's ultimate strength cannot be calculated by design mix alone. Rather, it is very much dependant on the degree to which it is consolidated. Our cast stone typically achieves compressive strengths of 6,500 psi (pounds per square inch), and more. It can attain 11000 psi or even more under ideal conditions, and can be consolidated to the point of being very nearly impervious to water absorption.
Runways extend deep into a vault-like structure which is lined with pipes. The pipes provide steam and moist cure the stones until the following morning. At that point, they are unloaded from the runways and taken into the yard where they are washed, rubbed, and etched to reveal the natural sparkle of the aggregate.
Every stone is washed, rubbed, etched, and carefully dressed to near perfection in a set of successive stages under close quality control inspection.
Once the stones are ready and approved, they are palletized and stored in the yard until they can be scheduled for shipping to the job site.
Despite constant shipping, the storage area occupies over 5 acres.
For wet cast stone, the production process is different. Larger wet pour cast concrete panels are produced in a separate adjacent area.They are cast in large forms on large platform tables. Here the procedure involves moving large quantities of concrete by way of hopper and overhead crane systems and then vibrational methods for concrete consolidation.