Bronk Ramsey, C., Higham, T. F G. and Pearson, J. A. (2011). Bone Pretreatment by Ultra-Filtration: A Report on Unintended Age Offsets Introducted by the Method. Fort Cumberland: Historic England. https://doi.org/10.5284/1047870. Cite this using datacite

Title The title of the publication or report Title:	Bone Pretreatment by Ultra-Filtration: A Report on Unintended Age Offsets Introducted by the Method
Series The series the publication or report is included in Series:	Historic England Research Reports
Downloads Any files associated with the publication or report that can be downloaded from the ADS Downloads:	englishh2-275156_1.pdf (1 MB) : Download
Licence Type ADS, CC-BY 4.0 or CC-BY 4.0 NC. Licence Type:	ADS Terms of Use and Access
DOI The DOI (digital object identifier) for the publication or report. DOI	https://doi.org/10.5284/1047870
Publication Type The type of publication - report, monograph, journal article or chapter from a book Publication Type:	Report (in Series)
Abstract The abstract describing the content of the publication or report Abstract:	Bone samples for radiocarbon dating undergo pre-treatment to extract original proteins from the bone and to exclude contaminants. Ultrafiltration is an extra stage in this process which further purifies the proteins and was first developed in 1988 (Brown et al 1988). In 2000 the Oxford Radiocarbon Accelerator Unit (ORAU) adopted this method for the pre-treatment of bone in order to improve the accuracy of its dating. Diagnostics of protein purity, including CN ratio, and background measurements all indicated that the method was working well. However, in 2002 it became apparent that the accuracy of dates, particularly those younger than 10,000 years old, was in some instances, being affected by the technique because of traces of contaminants from the filters themselves. A new method of preparing and testing the filters was developed (Bronk Ramsey et al 2004) and a programme of re-dating started. Despite the purity of protein resulting from the original method, the remaining filterderived contaminants (averaging 1.5%) were very different in age from the samples and this produced age offsets averaging 120 years. The effect was size dependent and greatest for samples yielding <10mg collagen. However, even samples >10mg collagen had an average age offset of 100 years and only above about 30mg does the average offset fall to 55 years. The effect is also seen to be very variable. The method did, probably, produce accurate results in comparison to other methods for bones between 10,000 and 15,000 years old, although producing slightly older rather than slightly younger dates. The only significant improvement was apparent in bones in excess of 15,000 years old. The implementation of new cleaning protocols (Bronk Ramsey et al 2004; Brock et al 2007) has resulted in a significant improvement in the routine application of the technique at ORAU.
Author The authors of this publication or report Author:	C Bronk Ramsey Thomas F G Higham J A Pearson
Publisher The publisher of the publication or report Publisher:	Historic England
Other Person/Org Other people or organisations for this publication or report Other Person/Org:	Historic England (OASIS Reviewer) Wiltshire and Swindon HER (OASIS Reviewer)
Year of Publication The year the book, article or report was published Year of Publication:	2011
Locations Any locations covered by the publication or report. This is not the place the book or report was published. Locations:	Site: Fussells Lodge Long Barrow County: Wiltshire District: Wiltshire Parish: CLARENDON PARK Country: England Grid Reference: 419150, 132460 (Easting, Northing)
Subjects / Periods Subjects / Periods associated with this record. Subjects / Periods:	NEOLITHIC (Historic England Periods) HUMAN REMAINS (Object England) NEOLITHIC (Historic England Periods) LONG BARROW (Monument Type England) FIELD SURVEY (Event)
Identifiers Identifiers associated with the publication. These might include DOIs, site codes, Monument Identifiers etc. Identifiers:	OASIS Id: englishh2-275156 OBIB: 91/2011
Note Extra information on the publication or report. Note:	A4 bound report of 23pp.
Source Where the record has come from or which dataset it was orginally included in. Source:	OASIS (OASIS)
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Created Date The date the record of the pubication was first entered Created Date:	02 Jul 2018

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