thumbnail_Plate Logo Transparent (1)

About six years ago I first heard of Argillite and its use in pre-historic Arizona. After traveling to multiple museums and looking at their jewelry collections, I noticed a beautiful and brilliant red stone that was made into necklaces, beads, pins, plugs, rings, and sometimes even projectile points. This stone instantly sparked my curiosity and I wanted to know more about it and its roots. I first talked to Dr. Andy Christenson about the stone and he told me it was a soft, mud like material that is easily carved, but also very durable. Christenson went on to tell me how important it was to the Prescott Culture in central Arizona. I immediately asked where the stone is located and he gave me a general direction. After our meeting, I instantly called a friend (Kiowa) and we went searching for it. Kiowa and I searched for an entire day and did not find anything but small pieces of artifacts. Finally, we got a good lead and found the mother load! We lugged ten gallons of stone over a mile back to our vehicles and have been working it ever since. In this article I will discuss the history of Argillite and Olivella use, and how to make a prehistoric style necklace. According to Zack Curcija (M.A), who wrote his masters thesis on jewelry and shell production in ancient Arizona, Argillite was exported throughout central AZ, most notably along the Verde River. “The production of jewelry seems to be restricted to settlements with a 30 km radius from the source, places like Argillite Mine Pueblo, Tuzigoot, and a few other sites in the Perkinsville Valley/Upper Verde area (Curcija).” With this said, at almost every Prescott Culture dwelling I have been to, I have seen small chunks of argillite—most completely worked and shaped out. I have also seen worked Argillite at Hohokam dwellings—these could have been traded or worked from a separate quarry. I am sure the Hohokam prized this stone as well—after all, they were a large culture that farmed over 75,000 acres and dominated prehistoric Arizona with heavy influence from Mesoamerica; but that is for a separate article.
Now that we discussed a very brief history with this stone, I want to explain how I make the prehistoric style necklace. We will first go over a few tools that I recommend—they are as follows:

Raw Argillite
Pot of warm water
Stone projectile point
Stone drill
Pine salve
Olivella shells
Cotton Rope and wax

Once you have the tools necessary, it is time to harvest Argillite. When mining Argillite, avoid any stone on the surface; as it is weathered and not suitable for production. You will need to dig and pull the stone out with a stone axe or metal chisel. When you pull out chunks of Argillite, test it to make sure it is not fractured—simply drop it on a hard surface and if it does not crack, the stone is good to use. Make sure you only harvest what you need; after all this is a rare stone.
Next, fill the bowl with water and saturate the sand stone surface. Throughout this process make sure the Argillite and sand stone is wet—you do not want to breathe in the dust. Much like flint-knapping, the objective of making jewelry is to reduce high spots and excessive mass. Every time I make a piece, I observe the stone and decide on what I want to craft. In this case we are replicating a disk shape. Continue by grinding the stone down until it has a square shape, and you have it thinned down a considerable amount. Next, remove the corners and make a round disk. Remember, this is a soft stone, so work slow.
Once the piece is thinned, it is time to cut into the stone and make grooves around the edges. Although we do not know what was used to carve into the original piece; however, I can say through experimentation on several pieces, a stone projectile point matches the shape of the cuts on the original. When cutting around the edge, support the center on the piece and cut just a bit deeper than the original artifact. As you work around the stone, you will notice the top, between each cut is flat—the original was not flat, but more rounded. Therefore, we must do the same. Simply break off a thin piece of sandstone and round the top and edges between each cut.
To finish the piece off I like to buff out the stone rasp marks—using a plant called horsetail is a perfect natural sandpaper. It is important to know, buffing the stone is not necessary, and in many original artifacts the rasp marks are still noticeable. In other words, it is entirely up to the artist if he or she wants rasp marks displayed. Next, lay the stone on a flat surface supported by buckskin. Take a stone chipped drill and towards the top of the piece, drill completely through the stone. This process should be used similar to creating fire by friction using the hand drill. When the hole is drilled in, I polish the stone with bear fat or a pine salve.
Now that our pendant is made, it is time to discuss Olivella shells, and how we can use them in a similar manner as the prehistoric people did. Much like Argillite, Olivella was heavily used by Sinagua, Hohokam, Prescott, and Salado peoples. Olivella was gathered white and brown in color, and was traded into prehistoric Arizona from the coastal regions of Mesoamerica and California. The shell that was mostly used for necklaces were small in size—although there are some examples using slightly larger shells. Furthermore, the shell and Argillite was strung on twisted vegetable rope and likely cotton rope that was grown in the Phoenix Valley (Hohokam territory).
First of all, it is quite difficult to find Olivella shells that are sold on the market. I obtain mine though trade or by traveling to Mexico and gathering them on the shore lines. Once they are gathered and dried, examine the shell; you will see there is an opening end and a closed tip. In order to string them, you must grind the tip off with the sandstone rasp. One by one you will see an opening appear—once again, go slow and check your work as soon as you see the opening. As you continue to grind, the opening will get wider. So how large should the opening be? This depends on the rope being used. As a general rule, the opening should be slightly larger than the circumference as the cotton rope .
When all the tips are ground off, the shells should be baked. As mentioned, original examples of Olivella shells were gathered white but also brown. The brown shells were baked to turn a beautiful white color—thus we need to do the same. Due to a lack of evidence, I can’t claim to know how past people baked the shells; however, from experimenting, I can say what works for me. This process is somewhat similar to firing pottery into a ceramic. First, I make fire by friction. Second, I place the shells in a ceramic bowl and keep it somewhat close to the fire that was created. Third, once the fire has died down and the shells are warm, I place the bowl on top of the hot coals with a stone slab covering the top. I will constantly check the shells to see if they have turned white. Finally, once they turn, the bowl is removed from the coals, the shells are removed from the hot ceramic bowl and allowed to slowly cool. This process takes about an hour to complete.
Now that we have the Argillite and Olivella carved and processed, it’s time to string everything together. Grab the cotton rope and wax it heavily—this helps from fraying and keeps the necklace rigid. Next, lash the pendant onto the rope by forming a larks head knot through the drilled hole. Proceed by separating the two cotton strands and add the shells to each side. I like to add a shell on one side of the rope, and then on the other. This will show you what size shell is needed to match the other. Finally, when you have the necklace length desired, pull the two ends of the rope together and make an over hand knot to complete the necklace.
In concluding this article, it is important to recognize the early people who occupied prehistoric Arizona and pioneered the use of Argillite and Olivella shells. The life-ways of the Hohokam, Prescott, Salado, and Sinagua cultures were not easy. A sudden and rapid lack of archaeological evidence in prehistory around 1400 – 1450 CE. supports this claim and further suggests their lives shifted. So what happened? This remains unknown. In Hohokam, a recent hypothesis and data suggests a weakening in the elaborate canal system that greatly effected their crops and the growth of Maize. This hypothesis also suggests the environmental stress to produce agriculture forced a migration amongst many Hokokam people. However, It is important to understand that prehistoric people did not disappear. Indeed, their descendants are still here and are recognized as modern day Natives who still use this technology in their cultural practices.


For more information on prehistoric jewelry, visit us at:
Special thanks to: Mark Swanson, Andy Christenson, Zack Curcija, Justin Parks, Peter Pilles, Arizona Archaeology Society, Smoki Museum, Sharlot Hall Museum, Pueblo Grande Museum.

Posted in

Jeff Martin

Leave a Comment