Novaculite 101

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Novaculite 101 2016-12-21T09:37:55+00:00

The History of Novaculite
Novaculite is a sedimentary rock composed of microcrystalline quartz, it is also recognized as a re-crystallized variety of chert. It is a high-purity silica, composed of more than 99 percent pure silica. The name is applied mainly to formations in Arkansas, Oklahoma, and Texas and is derived from the Latin word novacula, meaning razor stone. Novaculite is the rarest and finest abrasive stone in existence.

Found in depths of 250 to 900 feet, Novaculite was formed during the Mississippian and Devonian ages (about 350 million years ago). The stone naturally resists erosion and forms prominent ridges in the Ouachita Mountain range. The quantity of available Novaculite is immense. Whetstone quality novaculite is found predominantly in Garland and surrounding counties in the massive lower division formations. However, individual quarries exist from Little Rock in Pulaski County westward towards Hatton in Polk County. The amount of Novaculite that exists in these formations will allow for the continued production of sharpening and abrasive products for as long as the demand and profitability is there to sustain the industry.

Mining records indicate that settlers in this region began mining in the early 1800’s near Magnet Cove in Hot Springs County. Novaculite mining began in Arkansas intermittently from 1885 to 1905, and since that era mining has remained constant. Before the Europeans came to know Arkansas whetstones for their unique and superior sharpening and abrasive qualities, the Native Americans of the region gathered and quarried for Novaculite to make weapons and tools like arrowheads, spearheads, knives and axes. This process is known as Flint Knapping. There is evidence that trading between the tribes resulted in the distribution and use of novaculite hundreds and maybe thousands of miles from the source.

Red is Hot and Blue is Cold, Right?
What color is your Arkansas Novaculite Whetstone? Black? Blue-black? Charcoal Gray? White? Multi-color? Brown? Grey? Pink? Red? Sometime during the history of Arkansas whetstone production someone came up with what, at the time, seemed like a good idea. Arkansas stones come in a variety of colors, so why not associate a stone’s color with its grade (how hard or soft it is)? It wasn’t a bad idea in the beginning. Now, however we know that many of the same colors exist in more than one grade of stone so it gets confusing for the consumer and very limiting for the manufacturer.

Arkansas whetstones can be found with any of the following colors: pink, gray, rust red, black, blue-black, white, brown, purplish red. At times, one will find a combination of some of these colors in the same stone. Color however, does not distinguish the difference in the hardness of the stone. With a trained eye color can be used as one factor when distinguishing between grades of stone. But, only when used in conjunction with other indicators such as opacity, texture, luster, weight and mining formation. Using only the differences in color during the grading process is not a reliable indicator of stone grade.

At the Quarry is Where Grading Begins
Grade differentiation begins at the quarry. It is here that formations are inspected for mineralogical characteristics. Novaculite has a distinct appearance where it breaks—it resembles a shell (imagine looking at the surface edge of a scallop shell) known as a conchoidal fracture. The surface is smooth and will have a dull luster in the softer grades and a waxy, moving toward glassy luster in the finer grades. Being a sedimentary rock, the deposits are inter-bedded with some shale according to the Arkansas Geological Commission. For more information about stone grades see our page Stone Grades 101.

I got an A+ !
Arkansas stones are classified into grades of hardness, or density, and everyone does not call stones within grade categories the same thing. Not even government agencies refer to the stones the same way! You can see how the variety of names and colors could become a huge challenge in deciding which grade is best for your application. Educating yourself is the best method to ensuring you get what you want. If you are still unsure about what stone to purchase, please contact us. We would be more than happy to help you choose the best stone for your application.