The Jerusalem Post also covers the story, with additional details: Phylacteries were not colored black 2,000 years ago, new study reveals. Tefillin are small leather cases containing miniscule parchment scrolls inscribed with biblical verses. They are worn even today by observant Jews as part of their morning prayers (Judy Siegel-Itzkovich).
The underlying PlosOne article is open access:
Black surfaces on ancient leather tefillin cases and straps from the Judean Desert: Macroscopic, microscopic and spectroscopic analysesThis makes sense to me. The leather of the Dead Sea Scrolls sometimes has aged to a black color that is about the same as the ink. The ink is only visible on infra-red photographs. An example is 4QGenesisb, which I published in DJD 12.Yonatan Adler, Ilit Cohen-Ofri, Yonah Maor, Theresa Emmerich Kamper, Iddo Pinkas
Published: June 13, 2024
https://doi.org/10.1371/journal.pone.0303635Abstract
Tefillin are Jewish ritual artifacts consisting of leather cases, containing inscribed slips, which are affixed with leather straps to the body of the tefillin practitioner. According to current Jewish ritual law, the tefillin cases and straps are to be colored black. The present study examines seventeen ancient tefillin cases discovered among the Dead Sea Scrolls in caves in the Judean Desert. All seventeen cases display grain surfaces with a very dark, nearly black appearance. We start with a hypothesis that the cases were intentionally colored black in antiquity using either a carbon-based or iron-gall-based paint or dye. The aim of this study is to test this hypothesis by subjecting these tefillin cases to a battery of examinations to assess the presence of carbon and iron used as pigments, and of organic materials which may have been used as binding agents in a paint. The tests deployed are: (1) macroscopic and microscopic analyses; (2) multispectral imaging using infrared wavelengths; (3) Raman spectroscopy; (4) Fourier transform infrared spectroscopy (FTIR); and (5) scanning electron microscope (SEM) and energy dispersive X-ray (EDX) spectroscopy. The results of these tests found no traces of carbon-based or iron-gall-based pigments, nor of organic compounds which may have served as binders in a paint. These results suggest that our posited hypothesis is unlikely. Instead, results of the SEM examination suggest it more likely that the black color on the surfaces of the tefillin cases is the result of natural degradation of the leather through gelatinization. The Judean Desert tefillin likely represent tefillin practices prior to when the rabbinic prescription on blackening tefillin was widely practiced. Our study suggests that the kind of non-blackened tefillin which the later rabbis rejected in their own times may well have been quite common in earlier times.
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