Source: Dungeon Master's Guide

Wondrous item, legendary

This viscous, milky-white substance can form a permanent adhesive bond between any two objects. It must be stored in a jar or flask that has been coated inside with Oil of Slipperiness. When found, a container contains 1d6 + 1 ounces.

One ounce of the glue can cover a 1-foot square surface. The glue takes 1 minute to set. Once it has done so, the bond it creates can be broken only by the application of Universal Solvent or Oil of Etherealness, or with a Wish spell.