The ancient American Indians used many types of rocks and minerals in the making of their daily use tools and utensils.   In the Southeast these ranged from very hard granite and greenstone to almost as hard rhyolite and chert to relatively soft limestone and even softer steatite.  One stone that was apparently not often encountered by the prehistoric Amerindians, even though it was, and is today, found in parts of the region, is the shiny black rock that was occasionally used to make ancient Virginia Indian tools – obsidian.

Obsidian is not a true mineral in this region of almost countless different minerals.  It is instead an authentic natural glass formed by cryptocrystalline grains of silica in glass-like suspensions of the matrix.   It was formed as an extrusive volcanic igneous rock and could even be formed today from a volcanic eruption.  Obsidian was anciently produced when felsic lava cooled rapidly with a minimum of crystal growth and often was the result of the super-hot melted rock coming into contact with cool water.  It is normally found in the margins of rhyolitic lava waves or surges that are now simply known as lava flows. It is always found where rhyolitic eruptions have occurred and this volcanic heated rhyolite, that cooled relatively near the surface of the earth, lost its natural water content by steam and/or by becoming soaked in cooler liquid and became the vitreous obsidian. The make-up of the glass is primarily silicon dioxide, also known as silica or even more simply - sand.  It is chemically similar to granite and rhyolite in the fact that all were originally molten volcanic solutions of flowing minerals. This ancient stone was named for its similarity to the Ethiopian rock called obsius and is relatively soft being in the 5.0-5.5 range on the Ohm mineral firmness scale where the diamond is the most unbreakable stone on earth with a hardness of 10.0.  It is somewhat young, in geologic terms, with most extant specimens being formed less than 50 million years ago and is found throughout the world where volcanoes were or even are today.  In North America, obsidian is mostly found in the western half of the country where huge hillsides of the glass can be found. But in the region that today that is known as the Commonwealth of Virginia, there have been, in the remote past, over 100 volcanoes existing mostly in the western mountainous areas.  Some of these volcanoes were active up to 750 million years ago which was well before our continent was even formed.  Two, though, called Mole Hill and Trimble Knob, are still with us, though inactive today,  and are the youngest volcanoes in the eastern half of the continent at less than 48 million years of age.   The Appalachian Mountains, where these two are located, are at least 480 million years of age being formed before the super-continent Pangea was created around 300 million years ago.  No obsidian is older than the Cretaceous Period or 66 million years ago because the glassy rock is rapidly (again in a geologic age sense) destroyed or altered by heat, weathering or other natural processes to become fine-grained mineral crystals.

Since most of the ancient Virginia volcanoes are so extremely old, there remains today, very little to actually show where they once were.  Mole Hill and Trimble Knob are, in reality, only the remnants of the insides of primeval volcanoes.  The prehistoric American peoples must have accidently found the remains of these gaseous vents and discovered a quantity of the natural glass.  Obsidian is normally found mostly in an opaque and glossy solid black color but has been found in brown, red and infrequently in green hues and occasionally in a semi-translucent state in these colors.  It has also been found in a rock that is called snowflake obsidian where small particles of quartz or feldspar did not completely dissolve and now show up as tiny bubbles in the pellucid embedment.  It is a very good stone to make chipped tools because it breaks with conchoidal fractures with the result being extremely sharp edges.  In fact some modern flint knappers have produced obsidian scalpel-like tools that have proven to be much sharper than the steel ones normally used in medical surgeries.  It stands to reason that the Archaic nomads would have utilized this stone when they encountered it.

Few ancient chipped tools, which are made of obsidian, can be definitely attributed to being knapped in Virginia.  The ones that have been found were usually located in or near large flowing rills that come directly from the Blue Ridge and Appalachian Mountains.  Two such streams, known, as the Smith and Dan Rivers, that originate in the Blue Ridges and move into the Piedmont along the NC/VA border, could easily have brought, and still bring, many types of rocks and minerals from the mountains into the flatlands. These watery flows have, in fact, brought numerous categories of stones from the hills including chert, rhyolite, quartz, chalcedony, ferruginous sandstone and quartzite and possibly along came the occasional chunk of obsidian. All these stones were used by early Americans to flake into various tools and implements with the cherts and volcanic rhyolite being the minerals used the most by the prehistoric Indians in the Old Dominion state.  Some writers firmly state that obsidian is not found in Virginia but that does not explain the black natural glass points and knives that have been found near the area rivers. And it completely ignores the fact that ancient volcanoes were indeed active in the peaks of the western regions of the state.  Some scholars maintain that these obsidian tools were made from the black glass traded in from the Rocky Mountain sector of our country.  We do know that this trading was done in the Woodland Period into what is now Ohio and volcanic glass was acquired by the people we call Hopewell as early as 100 BC.  But most of the Virginia obsidian tools are from the Archaic Periods or 2,000 to 10,000 BC which was well before it is believed any extensive trading by the natives actually occurred.  Scientific analysis can supposedly determine if the black glass tools originated in what is now Utah or Idaho or in aged Virginia.  But how many ordinary collectors have the funds available for these very expensive tests.  And how many would consider the examinations necessary when a logical presumption is that true Virginia volcanoes created the natural glass which would be commensurate with early man utilizing this stone for the ancient Virginia tools made of obsidian.



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