Anna Very useful comment. Lorelei -----Original Message----- From: Anna Binnie [mailto:l...@binnie.id.au] Sent: Monday, February 13, 2017 6:30 PM To: Lorelei Halley <lhal...@bytemeusa.com>; 'Laurie Waters' <lswaters...@comcast.net>; 'Nancy Neff' <nancy.a.n...@gmail.com>; jeria...@aol.com; 'Arachne' <lace@arachne.com> Subject: Re: [lace] RE: Carbon dating of lace
I should add a few amendments to this. There are lots of factors that can cause measurements in dating with an error margin of upto 100 years and sometimes even more, these factors can include the fact that the lace could have been made from old thread, ie some one made lace with a thread they found at home that may be decades old. The dating can only be as accurate as the age of the thread not when it was made. Then other factors come into play, if the lace was washed or poorly stored in its life it could accumulate contaminants some of which could be carbon based and organic in nature. This could add to the uncertainty. Since bobbin lace has only been around since late 1400's at the earliest pattern books date to the early 1500's therefore bobbin lace was around before then, the oldest bobbin laces would be 500 -600 years old. The dating uncertainties could give you a date with a very large margin. However if you are looking at a piece of textile with embroidery such as needle lace or a piece of sprang that has a history to the Ancient Greeks then carbon dating can be quite accurate in the sense that it can tell you whether it is 1000 or 2000 years old or more recent. This form of dating can determine if a cloth is a forgery or the real deal. Carbon dating is based on a statistical analysis of the ratio of carbon 14 to carbon 12. As such it can be quite accurate but it won't be able to tell you with any certainty if the Lace is 100 years old or 200 years old. That is why I mentioned that lace is in the historic period and you would be better to date the lace using type, style and thread composition. Anna in Sydney where it has just started to rain On 14/2/17 9:45 am, Anna Binnie wrote: > The most reliable carbon dating is up to about 15,000 years. That is > about 3 half lives (carbon 14 half life is 5,740 years with an error > of > 30 years). So for lace it should be reasonably accurate. > - To unsubscribe send email to majord...@arachne.com containing the line: unsubscribe lace y...@address.here. For help, write to arachne.modera...@gmail.com. Photo site: http://www.flickr.com/photos/lacemaker/sets/
