"When the glue was dissolved, the researchers dated the first-century gospel in part by analyzing the other documents found in the same mask."
"Evans says that the text was dated through a combination of carbon-14 dating, studying the handwriting on the fragment and studying the other documents found along with the gospel. These considerations led the researchers to conclude that the fragment was written before the year 90."
"The team originally hoped the volume would be published in 2013 or 2014, but the date had to be moved back to 2015." [Update: It has now been reported that the publication has been delayed for another two years, that is, 2017.]
I'm looking forward to seeing the publication of this papyrus fragment, which is apparently slated for this year. The Live Science piece, written by Owen Jarus, was well done. Jarus even devotes a section to the controversy around destroying mummy masks and links to this blog. All in all, we are going to have to sit back and wait for the publication, which I am confident will give us many more details.