I also do not know the reason the tilma has not decayed, but I have studied this subject extensively over the last year. Throughout history, many people have had the chance to study the tilma, and some observers have concluded that the tilma is made from hemp fibers. Hemp fibers would easily last 500 years, thereby solving the puzzle.
So, the question for hundreds of years is whether the tilma is made of cactus/agave (quick decay) or hemp (500+ years stability). Over all these years, there has been only two scientific fiber analyses reported. The first, and likely the most laborious study was done at the National University of Mexico in 1946 by a biologist Isaac Ochoterena. His rigorous analysis concluded that the tilma was made from agave fibers.
The only other fiber analysis was done by a qualified scientist in 1999-2000, Professor John J. Chiment from Cornell University. He concluded that the tilma was made of hemp fibers.
Over the centuries, various people, usually artists have made conclusions about the fiber by use of only a magnifying glass. Many concluded agave, and some hemp, and the most recent observation in 1982 was during the last restoration of the tilma by Rosales. Using a 20 to 80X magnification, he concluded that the fiber was a hemp mixture.
So therefore, to date there are only two laboratory analyses performed, Ochoterena in 1946 and Chiment in 1999, with conflicting conclusions.
Now the rest of the story. Chiment did not publish his results, only because the fiber he tested was from a reliquary sample, which had no confirmed provenance. Ochoterena did publish his results, however, his sample was also from a reliquary sample without known provenance.
Conclusion, in the last 492 years, there has been no known sample removed directly from the tilma and sent for fiber analyses.
Therefore, that is why “Scientists can’t explain why Guadalupe tilma hasn’t decayed.” In scientific logic, this is known as an “Argument from Ignorance.” We still await the answer, is it hemp, or is it a miracle.
aleteia.org
