| Clue | Source | Date |
|---|---|---|
| Materials used to finish and shape workpieces through friction (9) | ||
| Cleaning substances (9) | ||
| Abradants | ||
| Polishing substances | ||
| No-nos for cleaning glass stovetops | New York Times | 28 Oct 2017 |
| No-nos for cleaning glass stovetops | ||
| Sandpaper and such | New York Times | 29 Nov 2015 |
| Sandpaper and such | ||
| They create a lot of friction | ||
| Emery and pumice | ||
| Grinders | ||
| Pumice, etc. |