The Jehoash Tablet’s inscription has become embroiled in controversy in an ongoing forgery trial in Jerusalem. The co-authors’ findings supporting its authenticity were recently documented in Archaeometric Analysis of the ‘Jehoash Inscription’ Tablet, published in the Journal of Archaeological Science [35 (2008) 2966-2972].
http://www.touro.edu/media/pr/releases/PR-Sandstone.asp