| Clue | Source | Date |
|---|---|---|
| Red colour found in the roots of the madder plant (8) | ||
| Red pigment from the root of the common madder plant (Rubia tinctorum) that became the first synthesised natural dye in 1868 (8) | ||
| Red dye pigment originally derived from madder root, with a name of Arabic origin | The Times Specialist Sunday | 09 Mar 2025 |
| Brazilian book out trashes dyeing matter | ||
| Colouring matter of the madder root | The Telegraph General Knowledge | 09 Aug 2015 |
| Red dye pigment | The Times Concise | 12 Jun 2015 |
| Darker shade of crimson |