Lead White or Lead Whites? Reconsideration of Methods of sefidāb-i-sorb Production in Iran. (2nd January 2019)

• Record Type: Journal Article
• Authors: Niknejad, Maryam; Karimy, Amir-Hossein
• Is Part Of: Studies in conservation. Volume 64:Number 1(2019)
• Page Start: 1
• Page End: 9
• Publication Date: 2019-01-02
• Subjects: Lead white -- laurionite -- phosgenite -- blixite -- historic sources -- Persian painting; Art objects -- Conservation and restoration -- Periodicals; 700.288
• DOI: 10.1080/00393630.2018.1457290
• Languages: English
• ISSNs: 0039-3630

Abstract

ABSTRACT: Lead white is widely used as a white pigment in the history of Persian painting. This paper focuses on three Persian treatises dated between the twelfth and the sixteenth century, which explained different manufacturing methods of lead white or sefidāb-i-sorb . Experimental reconstruction of each recipe to access the comprehensive meaning of the text and analytical studies with X-ray powder diffraction on products of recipes revealed white compounds other than the previously known products of hydrocerussite (Pb(OH)2 · PbCO3 ) and cerussite (PbCO3 ) in samples. Chlorine-containing raw materials mentioned in these recipes lead to the chemical products of laurionite (Pb(OH)Cl), blixite (Pb8 O5 (OH)2 Cl4 ), and phosgenite (Pb2 Cl2 (CO)3 ) in the final products. These data lead to the hypothesis of the discrepancy of the lead white pigment between Iran and Europe and a marked probability of other compounds in historic Persian lead white samples.