Earlier than the Earliest?

I was wondering, what are the chances that there are still yet undiscovered remanents of early buddhist texts that could be found and translated? Texts that are even older than what we have now. Are there any archeology type intiatives dedicated to researching where something like this might be and searching for it? I feel like I remember reading about some gold tablets that might exist or something like that.

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It’s a tantalizing possibility, but unfortunately it’s unlikely.

The oldest manuscripts we have now date back close to the beginning of the Common Era. We may well find other manuscripts around this time. But this is probably not long after the introduction of writing for Buddhist manuscripts, so it’s unlikely we’ll find manuscripts much older than this.

As to earlier texts, it’s certainly possible that there are undiscovered fragments in stone—sayings, quotes, perhaps a verse or two. But it’s not likely, as so far the stone inscriptions are thin on quotes, usually just repeating the same well known verse or two.

And finally, there could in principle be plates, possibly of gold. The commentary to MN 140 says that such plates were made, with lengthy inscriptions of Buddhist texts, and secured in a stupa. But whether this is true is unknown. In any case, for gold to survive the ravages of 2000 years of grave-diggers would be something of a miracle. Still, stranger things have happened.

The final problem is simply the state of Indian archaeology. Simply put, the resources of the Indian archaeologists is grossly inadequate for the massive amount of sites and materials, and the explosive pace of development and population growth.