Analysis Methods

            All ceramic artifacts within the sample were analyzed either on a general level for gray ware vessel body fragments and untypable white ware or a specific level for gray ware rim sherds, typable white ware, and all red and brown ware ceramics.  Refer to the description of the sampling strategy for more detail about selection of the analyzed ceramics.  Although some of these data are not discussed in detail here, all of the recorded attributes described below were integral to identifying the pottery traditions, wares, and types within the ceramic assemblage. 

Catalog Information

            Catalog information, including Site Number, PD Number, and Bag Number, were obtained from the artifact bag labels.  Within each PD and Bag Number designation, sherds were divided into lots based on similar attributes.  Analysis lots were assigned consecutive numbers within a PD and Bag Number designation.  Sherds selected for oxidation analysis were assigned Item Numbers that were consecutive for the Tommy Site assemblage regardless PD, Bag, or Lot. 

Ware, Tradition, and Ceramic Type

Based on the attributes recorded, sherds and vessels were assigned traditional ceramic types, such as Gallup Black-on-white or Mancos Black-on-white; ceramic traditions, such as Cibola or Northern San Juan; and ware categories, such as gray ware or white ware.  Pottery of the Anasazi culture is subdivided into traditions and types that represent specific geographic areas.  Not only can traditions and types be indicative of geographic locals of manufacture, but ceramic types evolve through time and are a useful tool for dating sites.    

Temper

As defined by Rice (1987:483), temper is “a material—mineral or organic, but usually nonplastic—added to a clay to improve its working, drying, or firing properties.”  Some tempering additives are specific to a geographic area, making the ceramic item easily identified as produced locally or nonlocally.  For example, trachyte temper (a greenish igneous rock also known as olivine basalt) is only available in the Chuska Mountains of northwestern New Mexico; thus, pottery with trachyte temper was produced at Anasazi sites along the slopes of the Chuska Mountains. 

Identification of tempering material was accomplished using a Meiji binocular microscope at a setting between 20x and 40x.  A fiber optic ring light was the light source for the microscope.  A small portion of a sherd was removed, exposing a fresh break to observe the tempering material.  Temper is one of several primary attributes for identifying ceramic types and frequently provides a probable source location for pottery.

Vessel Form

Based on sherd (pottery fragment) curvature, vessel portion (e.g., rim, body, base), and surface treatment, sherds were classified as originating from bowls, jars, effigies, and pipes, among other forms.  Body sherds generally are classified within the broad categories of bowls or jars.  Rim sherds, on the other hand, provide more information with which to assign specific vessel forms.  Jar rims may be placed into several categories including wide-mouthed jars, seed jars, and ollas.  Wide-mouthed jars are characterized by a wide rim orifice that is approximately the same size as the maximum vessel diameter.  Seed jars have a short, globular shape with no neck and a rim orifice that is significantly smaller than the maximum vessel diameter.  Ollas, on the other hand, are large vessels that have long, narrow necks and narrow rim orifices significantly smaller than the maximum vessel diameter.  Additional vessel types that may be encountered include pitchers, ladles, effigies, and other specialized forms.  Identification of vessel form is an important attribute for characterizing the functional aspects of a ceramic assemblage.

Vessel Portion

            Vessel portion was identified for all sherds and described the location on the vessel from which a sherd fragment originated.  Sherd fragments were classified as either representing the rim, neck, body, base, or appendage of a vessel.  Sherds representing a single vessel were grouped into a single category and assigned a reconstructible or whole designation. 

Pigment

Paint types were identified by several observable traits including color, reflectivity, texture, and degree of adhesion.  Paint identified on pottery commonly includes either organic (plant) or inorganic (mineral) pigments that were applied prior to the firing process.  Recording of paint type is often an important attribute in determining ceramic ware, series, and type. 

Exterior and Interior Surface Treatment

Surface treatment refers to the manipulation of the vessel surface prior to the firing process (Rice 1987; Shepard 1980).  These treatments may include slip, polish, paint, incising, and corrugation, among others.  Surface treatment is one of the primary attributes used for classifying a sherd or vessel within an existing typology.  Plain surfaces include those that were wiped or scraped with no other surface manipulation.  Corrugated surfaces were produced by indenting the exterior surface with a finger tip as clay coils were applied.  Polished surfaces were produced by rubbing with a polishing stone or other object having a smooth, hard surface, producing a sheen with polishing striations.  Slips were identified on a number of sherds and are characterized by a thin layer of clay applied over the vessel surface.  When viewed in profile, slips appear as thin lines of contrasting color and texture to the ceramic paste.  Painted designs were applied to slipped, polished, or plain ceramic surfaces. 

Postfiring Modification

Closer examination of sherds and vessels often reveals postfiring modifications that reflect changes in function.  It is common to encounter sherds that have been modified into pendants or tools, and, for example, jar fragments that have been modified into bowls or saucers.  Identification of postfiring modifications assists in further characterizing the range of activities that took place at a site and the role ceramic artifacts had in these activities.  

Use Wear 

Evidence of use wear on the interior or exterior surfaces of sherds or vessels provides additional data concerning the functional aspects of a ceramic assemblage.  Correlation between use wear and vessel form can provide information pertaining to a particular shape of vessel used for a specific function (Skibo 1992).  Use wear categories include exterior sooting, interior sooting or carbon deposits, interior mineral deposits, rim chipping, and basal abrasion, among others.  Because postdepositional wear and residues are common, use wear categories such as sooting and rim chipping may be the result of postdepositional activity as well as prehistoric use.  Thus, context and postdepositional disturbance are considerations relevant to interpreting these data. 

Vessel Appendage

Recording of vessel appendages also provides information concerning vessel function and type.  The location and style of an appendage indicates the type of vessel from which the sherd originated, such as pitchers, mugs, or bird effigy jars.  Vessel appendage categories include lugs, recessed handles, single coil handles, strap handles, and multiple coil handles.  Appliques are generally included under vessel appendages. 

Rim Radius and Arc

Rim radius and arc measurements are commonly used to estimate vessel size based on the curvature of individual rim fragments or partial vessels and to assist in estimating the minimum number of vessels present in a ceramic assemblage.  Rim radius and arc measurements are taken separately using a template similar to that illustrated by Rice (1987:223, Figure 7.9).  Rim radius is measured in cm and provides an estimate of potential orifice diameter of a vessel.  Rim arc is measured in one-degree intervals of a 360-degree circle to provide an estimate of the amount of vessel orifice circumference present.  Thus, rim radius provides an estimate of vessel orifice size and rim arc provides an estimate of the amount of the rim present and a means of evaluating the accuracy of the radius measurement.  The greater the amount or percentage of rim arc present, the more accurate the rim radius measurement.

Count and Weight

All sherds within PD, Bag, and Lot number designations were counted and weighed.  Sherd counts alone can be misleading depending on the size of the sherds and may result in an over- or under-estimation of potential vessel numbers.  Weight (g) provides a means of evaluating the interpretative potential of sherd counts and of compensating for the inadequacy of sherd counts in accurately representing the actual quantity of ceramics.