Ingredients: Iron sulfate, gallic acid (tannic acid), and water.
- Iron sulfate: This was typically obtained by dissolving iron scraps or cast iron in sulfuric acid.
- Gallic acid: This was extracted from oak galls (growths on oak trees caused by insects) or from sumac berries.
Process:
- The iron sulfate and gallic acid were mixed in a ratio of about 1:3 in water.
- The mixture was heated until the solids dissolved and a dark, bluish-black liquid was obtained.
- Gum arabic or other thickening agents were sometimes added to give the ink more viscosity and prevent it from feathering.
2. Logwood Ink:
Ingredients: Logwood extract, potassium dichromate, and water.
- Logwood extract: This was obtained by boiling the heartwood of logwood trees (Haematoxylum campechianum) in water.
- Potassium dichromate: This was used as an oxidizing agent to intensify the color of the ink.
Process:
- The logwood extract was mixed with water in a ratio of about 1:10.
- Potassium dichromate was added in a small amount (usually around 1% of the total volume).
- The mixture was stirred until the potassium dichromate dissolved and the color turned from red to purple-black.
3. Aniline Ink:
Ingredients: Aniline dyes, water, and solvents such as alcohol or glycerin.
- Aniline dyes: These were synthetic dyes derived from aniline, a chemical compound obtained from coal tar.
- Water and solvents: Water was used as the main solvent, while alcohol or glycerin was added in small amounts to improve the solubility and flow of the ink.
Process:
- The aniline dyes were dissolved in water or a mixture of water and solvents.
- The mixture was heated until the dyes dissolved completely and a homogenous solution was obtained.
These three types of ink were among the most commonly used in the 1800s. Other inks, such as carbon inks and copying inks, were also used but were less common.