The pipe stem date (using Lewis Binford’s formula) is 1746.67. Creating a Harris Matrix allows archaeologists to put excavation contexts in order from the bottom of the site to the top.We created a diagram capturing the relationships of the layers (or strata), which was digitized and made available for download on This dating technique can provide a more accurate measure for the date after which a particular layer or phase was formed by calculating the beginning date of manufacture of the latest dating artifact in an assemblage or sub-assemblage.For example, if you had a handful of coins from a particular layer, dated 1750, 1775, 1800, and 1802, the TPQ (or ) is 1802.
Historical archeologists excavating English colonial sites often find pieces of white clay smoking pipes on their sites. The earliest pipes, dating to about 1600, had stems with 9/64-inch diameter bores.
By 1800 this diameter had decreased to 4/64 of an inch.
Dates allow archeologists to connect a site/deposit to a specific time period, allowing us a better understanding of the past.
Historical archeologists have an advantage when it comes to dating because of the written historical record.
Although an object may have a known manufacturing date, this does not mean that the object was used when it was made. A hand-me-down set of dishes you inherited when you went to college?
A known manufacturing date tells us that the site cannot be older than the object, but that doesn’t mean that the site is not a lot younger. The presence of these things can throw off the mean ceramic date. In an ideal world, every deposit would contain a dated penny.
These measures can refine TPQs by removing ceramic outliers that may have been introduced through excavation error or disturbance.
The clay pipe industry expanded rapidly as tobacco smoking gained popularity in both England and America. Harrington studied the thousands of pipe stems excavated at Jamestown and other colonial Virginia sites, noticing a definite relationship between the diameter of the pipe stem bore—or hole—and the age of the pipe of which it had been part.
Also provided are two other TPQ measures, TPQ95 and TPQ90.
TPQ95 estimates the date after which the deposit was formed based on the 95th percentile (or 90th for TPQ90) of the beginning manufacturing dates for the sherds from that layer.
is that bore diameters decreased to compensate for an increase in the length of the stems. Another theory among archeologists for the decrease in bore diameters is that tobacco became more refined, meaning the pieces of tobacco were smaller. Or are there other reasons that could account for the decrease in bore diameter? Is it because people break them off because the stem gets dirty?