The tests were performed in different laboratories within the NITE-CRIME (Natural Isotopes and Trace Elements in Criminalistics and Environmental Forensics) European Network, using a variety of LA-ICP-MS systems. The main objective of these interlaboratory tests was to cross-validate the various combinations of laser ablation systems with different ICP-MS instruments. The first study, which used widely available glass samples such as the NIST SRM 610 and NIST SRM 612 reference glasses, produced deviations up to 60 percent in the determined concentrations of trace elements among the laboratories. Subsequent discussion among the laboratories and the production of new glass reference standards, which are presented in this article, established an improved analytical protocol that was tested on a well-characterized float glass sample from the BKA Wiesbaden collection. Following this protocol, interlaboratory tests produced improved results for nearly all elements (a deviation of less than 10 percent), showing that LA-ICP-MS can produce absolute quantitative measurements on major, minor, and trace elements in float glass samples for forensic and other purposes. 7 figures, 3 tables, and 31 references