As far as I'm aware on the Shroud of Turin for every 'expert' that says it is unexplained another ten 'experts' say it is. There's so much noise surrounding that particular piece of cloth I don't think anyone can really say either way. And probably never will; the Church is extremely careful about who they allow to look at in any detail. And remember there is no record of it - none - before about 1350. A period when the production of false relics was probably one of the biggest money making industries in Europe.
Also remember that just because we can't replicate it now doesn't mean it couldn't be done back then. Just because we can't fit huge blocks of stone together as well as the Incas did doesn't mean it was done for them by aliens. We just don't know what techniques they used any longer.
Also remember that just because we can't replicate it now doesn't mean it couldn't be done back then. Just because we can't fit huge blocks of stone together as well as the Incas did doesn't mean it was done for them by aliens. We just don't know what techniques they used any longer.