Following on from last week’s blog, today’s post takes a look at how we date ceramic artefacts, specifically the plates, cups, bowls and saucers we find so often in Christchurch. Many of the issues I mentioned last week with regard to glass bottle dating also apply to ceramics (and all artefacts, really), but there are some that we encounter more frequently depending on the type of material we’re looking at. With 19th century pottery, one of the more common obstacles is the difficulty of dating artefacts from the style of their decoration, along with the ever-present problem of ‘time lag’ (more on this later).
Ceramics are an interesting challenge when it comes to artefact dating, since it’s quite difficult to use details of manufacture to figure out when they were made. Some vessels have maker’s marks or ‘backmarks’ stamped or printed on the back with the name of the pottery manufacturer (and these are subject to all the same problems as with bottle marks), but often we may not actually find that piece of the plate or teacup. Other times, frustratingly, we find artefacts without any mark at all.
In these cases, dating the fragments of pottery that we have is tricky, since many 19th century ceramics don’t have very much visible evidence for dateable changes in manufacturing technology. This is thanks to the actual methods of manufacture as well as the fact that most of the notable developments in ceramic manufacturing occurred in the late 1700s and early 1800s, leaving production techniques largely unchanged for most of the 19th century. Unfortunately for the archaeologist working with material from the 1850s onwards (as in Christchurch), a date range of 80 to a 100 years for a site is pretty much the same as no date at all.
Alternatively, we can try to use changes in decoration and style to date artefacts to specific decades. Of course (because an archaeologist’s job is never easy!) there are problems with this as well. Although there are documented changes in the popularity of different types of decoration and different styles of pattern over time, many of these fashion trends also occurred in the first half of the 19th century (Samford 1997). For those of us working in Christchurch, that’s not really that helpful. Much of the information about ceramic fashions is also specific to Britain or America and those fashions weren’t necessarily popular at the same times or even at all in New Zealand (although there are some exceptions; Woods 2011). This is especially relevant when we take into account the time it would take for new patterns and styles to not only make it to New Zealand, but become popular here, particularly when we consider the distances they had to travel.
As with glass bottles, almost all the ceramic artefacts found on 19th century archaeological sites in Christchurch (and New Zealand) were made in England and Scotland and imported into New Zealand (mostly from Staffordshire in England). As I mentioned last week, this means that when we’re figuring out a date for these artefacts, we have to take into account the time it would have taken for these objects to reach New Zealand in the first place. This ‘import delay’ (the time involved in the storage and transportation of goods from overseas manufacturers to Victorian Christchurch) is just one of the components of a broader issue in archaeological dating known as ‘time lag’, which I touched on briefly last week with the discussion of bottle reuse and an artefact’s ‘uselife’.
Time lag is a phrase used by archaeologists to encompass every stage in an artefact’s life, from its manufacture to its eventual disposal (and entry into the archaeological record). One archaeological model for time lag includes the amount of time an item might spend sitting on a shelf at a wholesaler and/or retailer and transportation between these places, along with the actual uselife of the object and the potential for the curation (i.e. heirlooms) and recycling (Adams 2003: 41).
As well as coming from overseas, with all of the delays involved in that, many ceramic vessels are intended to be used over and over again for an indefinite period of time. To add to this, many people in the past may have kept ceramic vessels as heirlooms or display pieces for a very long time. I know that my family still owns plates and teacups that originally belonged to my granny – if we were to throw them out now, in 2013, their original date of manufacture would have absolutely nothing to do with the date at which they were discarded, or the period for which they were in use.
It’s not all hopeless though. As with the bottles, manufacturer’s marks are a good place to start and some archaeologists have come up with estimates for the amount of time we should be accounting for when we date the table wares and tea wares we find on 19th century sites. The discussion and method behind those estimates is way, way too detailed to go into here, but, in an American context, the average duration of time between an object’s manufacture and discard has been calculated to be anything from 15-25 years (Adams 2003). Potentially more or less, depending on the characteristics of the site in question and a wealth of different variables. Unfortunately, this is an American estimate, so we have to be careful applying it to New Zealand sites, but it certainly makes apparent the caution that’s necessary when using the date of artefact manufacture to determine the age of an archaeological site or assemblage.
Although I’ve focused on ceramics in the post, the issues I’ve mentioned are ones that apply to all material culture recovered from archaeological sites – shoes, clay pipes, stoneware jars, nails, bolts, matchboxes, etc. It’s never just as simple as looking at an object and knowing where it came from and when it was made. As I mentioned last week (and will mention again, because it’s important), the when and the where are only truly useful and interesting when they’re joined by the how and the why and the who.
Adams, W. H., 2003. Dating Historical Artefacts: The Importance of Understanding Time Lag in the Acquisition, Curation, Use, and Disposal of Artefacts. Historical Archaeology 37(2): 38-64.
Samford, P., 1997. Response to a Market: Dating English Underglaze Transfer-Printed Wares. Historical Archaeology 31(2): 1-30.
Woods, Naomi. 2011. Pakeha Ceramics as Dating Tools. Archaeology in New Zealand 55(2).
The Potteries, n.d.. A History of Stoke-on-Trent. [online] Available at http://www.thepotteries.org.