I would like to venture a guess that nearly all collectors have at one time or another purchased an item which at that time we were completely enamored with only to place it in our collection and wonder if we had possibly made a mistake in buying it. Is it authentic? We have been diligent in keeping our collection clean and free of fake items, we asked the right questions and even had other knowledgeable collectors give an opinion concerning the piece; but the feeling that a problem still exist lingers in the back of our mind.
Today we have the technology available to put that uneasy feeling to rest. I.L.S. [INFRARED LASER SPECTROMETER] is a patented technology used in determining authenticity in stone artifacts. A full technical description is given online [Wally U.S. PATENT # 8134133]. But in layman’s terms fluorescence, or light values, are being measured by stimulating the artifact with a laser. An infrared laser has been found to be very effective in causing high energy electrons, which have accumulated within the lattice structure of the stone due to exposure to radon, to fall to lower energy states. When they fall, photons are emitted and then by using a detector [charged- couple device] in conjunction with the laser the emission from the photons may be measured and recorded in the form of a graph.
This information can then be compared with known examples stored within a data base. Authentic ancient artifacts come in contact with radioactive radon dissolved in rain water from the environment. A data base is built using authentic samples of known lithic types. Point bases from various lithic types [Upper Mercer, Flint Ridge, etc.] and fragmented slate items are most often used in gathering this information. Thousands of readings are taken to establish an average reading along with a threshold. This is a very time consuming accomplishment but the amount of data gathered can be invaluable and put to use in several different ways. Not only can authenticity be established, but in some instances lithic types may be determined.
This was the case when materials from the Lamb Clovis Site located in Western New York State were examined with the laser and then compared with data base materials. This allowed for not only establishing the lithic types that the ancients were using but also their possible travel routes to acquire these materials. These routes could then be plotted due to the known present day sources of these materials such as Flint Ridge, Upper Mercer and Onondaga which were recovered at the site.
Now I would like to address some thoughts and common misconceptions concerning I.L.S.
#1: When using the laser an apple must be compared with an apple –THIS IS TRUE, meaning that lithic types must be compared with the same type lithic. Upper Mercer only compares with Upper Mercer and Flint Ridge can only be compared with Flint Ridge material.
#2: Artificial patination [shoe polish, dye, wax, ect] will fool the laser. THIS IS FALSE- artificial patination will give readings which will not compare with the authentic ancient examples stored within the data base. In addition, the laser is designed to take readings subsurface into the lattice of the stone. Artificial patination will cause artificial readings.
#3: The laser will date an item? YES & NO – The laser is designed to do relative dating, meaning that when an item is tested for authenticity it is being compared with known examples stored within the data base. Again apples to apples comparison must be done. If, for example, we test a Paleo point made from Coshocton material and then test an Archaic point made from Coshocton material a difference will be noted in the readings. The Paleo will test at a higher reading than the Archaic point due to longer exposure to the environment. But, if we were to test a Paleo point made from Coshocton material and try to compare it with an Archaic point made from perhaps Flint Ridge material the Archaic point would test at a higher average. This is due to the difference in lithics and not age. Flint Ridge cannot be compared with Coshocton material since each has its own unique characteristics. The laser can determine antiquity in an item and then we know by type [Clovis, dovetail, etc.] what age the item is believed to be by placing it within the accepted date ranges obtained by C-14 dating methods.
#4: In order for the laser to be used a sample is removed from item. THIS IS FALSE! All testing is accomplished by non-destructive means. No damage is ever done to an item being tested –EVER!
The materials we are able to test at this time are from the following states: Illinois, Indiana, Ohio, Kentucky, Georgia, Missouri, Arkansas, Mississippi, Tennessee, Alabama, West Virginia, Edwards chert from Texas and Onondaga from New York.
We all collect for various reasons, but I believe that most collectors have several things in common, such as when we hold an artifact in our hands we think not only about who was the person that made it but also how it was used in their daily lives. We want to know the truth about these ancient people and the items that they left behind and technology can help accomplish this.
Additional information: Paper prepared by Dr R. M. Gramly for the ASO, May 19th meeting, Columbus