The main takeaway of the ToI article is the response of two specialists who were willing to go on record. Christopher Rollston's reaction was very close to mine:
“The published images reveal some striations in the lead and some indentations (lead is, of course, quite soft and so such things are understandable), but there are no actual discernible letters,” Prof. Christopher Rollston, an expert in Northwest Semitic languages and the chair of the department of Classical and Near Eastern Languages and Civilizations at George Washington University, wrote in an email. “This article is basically a text-book case of the Rorschach Test, and the authors of this article have projected upon a piece of lead the things they want it to say.” ...On his e-mail list, Joseph Lauer points to a Facebook exchange between Lawson Stone (whom I don't know) and Peter van der Veen, one of the authors of the Heritage Science article. Stone raises a number of good points, including the same orthographic concern I raised and more. Joe also notes that Peter van der Veen has further interactions and comments on his Facebook page.“I don’t accept all the interpretations that were suggested in the article, and I plan to publish a different opinion in an academic journal,” said Bar Ilan University Prof. Aren Maeir, declining to elaborate further. Meir published the open letter criticizing the announcement of findings in the media prior to academic review on his blog last December.
The Jerusalem Post has an article on the story too, but it just repeats the claims of the Heritage Science article without critical analysis: Ancient tablet found on Mount Ebal predates known Hebrew inscriptions. ‘You are cursed by the God’: Israeli-European team of scientists performed X-ray tomographic measurements with different scanning parameters to reveal the hidden text (Judy Siegel-Itzkovich).
My view? It is possible that there are some letters on the "Inner B" surface of the interior of the object. I'm not sure there are, but I would not rule it out entirely.
As for the overall readings proposed in the article, the problems with the spelling (orthography) of the word "curse" (ארור), which I noted, as well as of Yahu (יהו) and "you" (אתה), which Stone adds, raise serious difficulty with the decipherment. Internal and final vowel letters in Northwest Semitic inscriptions are not used until long after the date assigned to this supposed inscription. (The few Ugaritic examples of internal vowel letters proposed in connection with n. 29 do not correspond to normal Ugaritic orthography and have plausible other interpretations.)
I am not persuaded by the case presented in the article for the reading of the inscription as a whole, if there is an inscription.
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