This article is a scientific examination of two metal plates found in 1986 in present-day Romania. The Latin text on the plates dates them to the year 109, in the reign of the emperor Trajan. The authors explain how the authenticity of the two plates was determined and describe the plates' physical composition. They determine that the metallic composition of the plates compares favorably with ore sources of Roman coins and metal objects. The content and significance of the plates are described in an article by John W. Welch and Kelsey D. Lambert in the same issue of BYU Studies.
Dorais, Michael J. and Hart, Garret L.
"A Metallurgical Provenance Study of the Marcus Herennius Military Diploma,"
BYU Studies Quarterly: Vol. 45
, Article 9.
Available at: http://scholarsarchive.byu.edu/byusq/vol45/iss2/9