Saltpeter cave in Newton County is an archeological site that has the potential to shed new light on the Archaic Period in the Ozarks because of its deep, stratified archeological deposits and the modern methods that were used in its excavation.

Saltpeter Cave in Newton County in 1968.

The name of the site comes from its use as a saltpeter mine during the Civil War.  Saltpeter, or saltpetre, is another name for the chemical potassium nitrate which is used to make gun powder. The saltpeter found in caves is not a geologic phenomenon, but comes from the buildup of bat droppings, sometimes called guano, on cave floors. This site is a true cave rather than a rock shelter and with its large opening and tunnels beyond it is a perfect environment for bats. This cave was mined for bat guano that was processed into saltpeter which was then used to make civil war munitions.

It might seem that this mining would would disqualify Saltpeter Cave as an important archeological site because it would impact the stratigraphy. However, due to the depth of the deposit (at least 14 meters remained undisturbed in 1969) and the fact that parts of the cave were not affected by the mining process, significant portions of the cultural deposit remained intact.

It was probably first visited by archeologists in the 1930s when Samuel Dellinger’s crews from the University of Arkansas Museum visited what they called Hale Cave. Because the 1930s field records are not very precise about location, there is some possibility that this site has been confused with another cave on the same creek, but the descriptions from the field records seem to match what is now called Saltpeter Cave. The artifacts from these efforts are still housed in the University of Arkansas Museum Collections.

An example of the deep deposits at Saltpeter Cave. This is a profile drawing on test Unit E. It is over 4 meters deep.

In the following years the site was looted. We do have some record of a human burial that was removed from the shelter in the early 1960s. An avocational archeologist named Gene Waters was able to view the artifacts associated with the burial and talk to the person who removed the skeleton from the cave. The burial was semi flexed and had many associated artifacts including several items made from marine shell imported from thegulf coast. Two marine shell earspools, large earrings commonly worn in the Mississippi Period, were found near the skull and many small shell beads were found in a position that suggested they had been worn as a necklace. Several arrow points were found with fragments of what may have been a leather bag. In addition, half of a shell tempered ceramic jar was recovered.  All of the artifacts found in the burial seem to indicate a Mississippi period date. The Marine shell would have been a relatively rare, and therefor valuable, commodity and may mean that the person buried with these items held an important in his or her community.

In 1969 Ken Cole, the research station archeologist working at the Arkansas Archeological Survey’s Russellville station, visited Saltpeter Cave for the first time with local resident Jack McCutcheon and became interested in conducting excavations at the site. Cole spent two field seasons conducting excavations at the site. Four of the excavation units they dug formed a line from the front to the back of the cave.  The archeologists made detailed drawings of the soil that formed the vertical walls of these units. Archeologists use these kinds of drawings, called profiles, to understand how the soil was deposited.  Many of the color and texture changes in soil on archeological sites are cultural. archeologists can for example see places Native Americans made hearths.  The burned soil under and around the fire changes color and texture.  Sometimes ash, or even pieces of charcoal are still present. These kinds of small details help with the interpretation of what life was like in the past. The precise records and the modern techniques used at Saltpeter Cave mean that the amount of information from this site is far greater than the information that was collected in 1930s era bluff shelter excavations.

The deep deposits at Saltpeter Cave, 1970.

Even more exciting to archeologists, a total of 43 C-14 samples were collected—7 in 1969 and 36 during the 1970 excavations. These are bits of charcoal large enough to be useful for radio carbon dating. The combination of precise record keeping, including drawings of both the walls and floors of the excavation units means that we know exactly where these samples came from and what artifacts were found near them. Context is important because this common archeological dating technique can only be used on once living, and therefore carbon bearing, material.  We have to find stone or ceramic artifacts in close association with plant (or in some cases animal) materials that we assume are the same age as the other artifacts.  We can then run a carbon date on the plant material and use it as a proxy for the age of the stone or ceramic artifact.

The depth of the units in Saltpeter Cave means we can get a glimpse back in time at least 8,000 years. It is possible to see changes in technology through time as the shelter continued to be used for thousands of years. The deeper deposits which represent the Archaic Period are the least disturbed part of the site which means they have the potential to give us the most information.  The collection may provide archeologists with new information on the Archaic Period because of its combination of precise records and abundant of Archaic Period stone tools with associated carbon samples.

Early Archaic rojectile points recovered from one 10 cm level of one test unit at Saltpeter Cave.