Mean Ceramic Date Formula

Mean date 1771 1758 1760 1760 for each type multiply the median date times the frequency 1771 x 31 1758 x 22 etc add these products divide the total by the total number of sherds in the assemblage the result is the mean ceramic date x fre uenc 31 sherds 22 sherds 56 sherds 17 sherds 126 sherds product 54 901 38 676 98 560 29 920 222 057.

Mean ceramic date formula. Common examples are earthenware porcelain and brick. The mean ceramic date mcd of an assemblage is a point estimate of the occupation of a site calculated based on the frequency and date range of types present most often used in historic archaeological contexts. He intended this to give an idea of most likely occupation date of site or context. The mcd is calculated by multiplying the number of sherds of a given type by the mid point of the date range for.

The article concludes that there is currently not enough data to determine whether or not the formula is useful or not. 1977 pioneered a measure of central tendency in assemblages of datable ceramics from historical sites in eastern united states. The crystallinity of ceramic materials ranges from highly oriented to semi crystalline vitrified and often completely amorphous e g glasses. Porcelain ˈ p ɔːr s əl ɪ n is a ceramic material made by heating materials generally including a material like kaolin in a kiln to temperatures between 1 200 and 1 400 c 2 200 and 2 600 f.

This change in diameter may have occurred because pipe stems became longer through time requiring a smaller bore. The mean ceramic date for an assemblage is estimated as the weighted average of the manufacturing date midpoints for the ceramic types found in it. These stratigraphic dates have been further verified through the application of documentary information south s 1972 1974 mean ceramic date formula and binford s 1962 mean pipestem dating formula. The toughness strength and translucence of porcelain relative to other types of pottery arises mainly from vitrification and the formation of the mineral mullite within the body at.

A mean ceramic date offers a quick and rough indication of the chronological position of a ceramic assemblage. By 1800 this diameter had decreased to 4 64 of an inch. The mean dates are assigned importance according to the quantity of each pottery type at the site. This article reviews the use of south 39 s mean ceramic dating formula and its use in dating historic sites in ontario.

An average of the mean dates is taken and the date that results should approximate the middle period when the ceramics were deposited deetz 1996 25. Louis binford later devised a mathematical formula to refine harrington s method deetz 1996 27. The weights are the frequencies of the respective types in the assemblages.