Electron microscopy requires the use of resin-embedded samples in order to obtain ultra-thin sections for imaging. However, the identification of these resin capsules and molds can be challenging, as traditional inks will run or smear during the embedding process. This can often lead to sample mix-ups or loss of information. This article describes a novel identification solution, ResiTAG™, specifically designed for use with resin capsules and molds. The article details how this chemical-resistant label can be incorporated into the sample preparation process.