Granite Facts (continued)
Crushing Strength
In compressive strength, ten samples of Elberton granites from seven separate quarries averaged 23,450 pounds per square inch (p.s.i.). Testing showed no significant difference to indicate granites from one producing area are more durable; all have adequate strength for any memorial or structural use For example, on the Washington Monument, the load bearing requirements for stone is equal to 600 p.s.i.
Monumental Stone Characteristics
Not all granites are classified by the U.S. Bureau of Mines as suitable for "monumental stone." According to the Bureau's standards for "Class 1" granites, they must meet exacting requirements such as uniform texture and color, freedom from flaws and general suitability for polishing and carving as well as resistance to weathering. Elberton blue-gray granites meet these requirements in every respect.
Endurance
Tests conducted by the Georgia Insitute of Technology on Elberton granites confirm an analysis made by the Bureau of Mines when testing all recognized "monumental grade granites" as quoted in Information Circular 7720; "While many trade names are applied to memorial stones and prospective users may raise questions as to whether these named varieties or types are superior to others, the Bureau of Mines has no data indicating that any of them is more enduring than any other. In fact all of the monumental granites produced by reputable firms in the well-known regions last so long with so little visible change that the factor of endurance should scarely be given consideration in making a choice. Selection may therefore be made on the basis of color, texture, design, and workmanship that best suit individual tastes."
For more information on granite and memorialization, please contact the Elberton Granite Association for a copy of the free publication "What is Granite?". When contacting the E.G.A., be sure to include your name, company name (if applicable), mailing address, city, state and ZIP code.