Is it? If you wanted to store something for 50 years which would you chose? 100 years? 1000? A million? It seems hard to beat engraving in stone. Possibly fill

Is it? If you wanted to store something for 50 years which would you chose? 100 years? 1000? A million? It seems hard to beat engraving in stone. Possibly fill the groves with something. 3d printing is perhaps good enough.