Making ink from soot is one of the oldest writing technologies in human history, and the process is surprisingly straightforward: collect soot from an incomplete flame, grind it fine, and mix it with a water-based binder. The resulting ink, traditionally called lampblack ink or carbon ink, produces a deep, permanent black that has survived on manuscripts for thousands of years. Here’s how to do it yourself.
Choosing Your Fuel Source
The quality of your ink starts with the fuel you burn. Oily and resinous materials produce the best soot. Pine pitch and other conifer resins are traditional choices that yield rich, dark carbon. Olive oil and sesame oil burned with a wick also work well. Candles can produce soot, but plain paraffin candles generate less of it and may contain waxy impurities. Beeswax candles aren’t ideal either, as they burn too cleanly.
The key principle is incomplete combustion. You want a smoky, sooty flame, not a clean one. A large, lumpy, or overly long wick encourages this by starving parts of the flame of oxygen. If you’re using an oil lamp, a thick cotton wick that extends well above the oil surface will throw off plenty of black smoke.
Collecting the Soot
The simplest collection method is holding a metal plate, ceramic dish, or flat stone a few inches above the flame. The rising soot deposits in a soft, dark cake on the underside of the surface. You’ll need to brush it off periodically with a feather or soft brush and collect it in a clean, dry container.
A more efficient setup uses a small stone or brick arrangement, like a miniature table, with your fuel burning underneath and a collection plate on top. For oil lamps, a tin funnel suspended above the flame funnels the smoke upward, where it collects in light, mushroom-shaped deposits of pure carbon at the top of the cone. One old technique repurposes a tuna can: leave the lid partly attached and bend it down into the oil to serve as a wick ramp, then place your collection surface above.
You can also interrupt the flame itself to force incomplete combustion. Placing a scrap of slate or a thin piece of metal partway into the flame disrupts airflow and increases soot output. However you set it up, expect the process to be slow. Collecting enough soot for a small jar of ink can take several hours of steady burning.
Purifying the Soot
Raw soot often contains traces of grease and unburned oils, which will prevent the ink from mixing and drying properly. To clean it, pack the collected soot into a small sealed tin (like an Altoids tin) and place it in a hot fire. The sealed container creates an oxygen-free environment that burns off the oily residues without consuming the carbon itself. After cooling, the resulting powder should feel dry and light rather than greasy or clumpy. This step isn’t strictly required, but it noticeably improves the final ink.
Grinding the Soot
Even after collection, soot particles tend to clump together in aggregates that won’t dissolve smoothly into liquid. Grinding breaks these clumps apart and produces a finer, more uniform pigment. The traditional tool is a glass muller on a glass or stone slab. You place a small mound of soot on the slab, add a few drops of your binder (more on that below), and work the muller in slow, firm circles. The pressure shears the clumped particles apart and replaces trapped air with liquid.
Carbon black is stubbornly resistant to dispersing. Unlike mineral pigments that break down quickly, carbon particles cling to each other and take patience to separate fully. Expect to spend 10 to 20 minutes of steady mulling before the mixture feels smooth. If you don’t have a muller, a smooth, flat stone and a rounded rock will work, or even the back of a spoon against a ceramic plate. The goal is sustained pressure and friction. You’ll know you’re done when the mixture looks glossy and even, with no visible grains.
Mixing the Ink
The binder is what turns loose soot into functional ink. The most common and historically proven binder is gum arabic, a natural tree resin sold as crystals or powder at art supply stores. Dissolve gum arabic in warm water at roughly a 1:2 ratio (one part gum arabic to two parts water by volume), stir until clear, then strain out any undissolved bits. This creates a slightly viscous liquid that holds carbon particles in suspension and helps them adhere to paper.
Start by adding your ground soot to the gum arabic solution a little at a time, stirring thoroughly. The ratio depends on how dark you want the ink, but a good starting point is roughly one part soot to four or five parts binder solution. Too much soot makes the ink thick and gritty. Too little produces a pale, watery gray. Test on scrap paper as you go and adjust.
Carbon particles naturally repel water, which makes them prone to floating on the surface or settling to the bottom. A tiny amount of a surfactant, something that reduces surface tension, helps the particles mix in and stay suspended. Ox gall is the traditional artist’s choice: it loosens the attractive force between pigment particles and prevents clumping. A single drop per ounce of ink is usually enough. A tiny drop of dish soap can substitute in a pinch, though it may affect how the ink interacts with certain papers.
Making the Ink Waterproof
Basic lampblack ink made with gum arabic is water-soluble. Once dry on paper, it will smear or wash away if it gets wet. This is fine for many uses, and it’s actually desirable for some brush painting techniques where you want to re-wet and blend.
If you want permanence, add a small amount of shellac to the mixture. Shellac is a natural resin (sold as flakes at hardware or art supply stores) that becomes waterproof when dry. Dissolve shellac flakes in a small amount of alcohol, then stir this solution into your finished ink. Commercial sumi inks use this exact approach: vegetable oil soot combined with shellac for water resistance. Start with a conservative amount, roughly a half teaspoon of dissolved shellac per ounce of ink, and test. Too much shellac makes the ink thick and can clog fine pen nibs.
Egg yolk is another historical option. A small amount of beaten egg yolk mixed into the ink acts as both a binder and a mild waterproofing agent, essentially turning the ink into a thin tempera. The downside is shelf life: egg-based ink needs to be used within a day or two before it spoils.
Storage and Shelf Life
Finished lampblack ink stores well in a sealed glass jar. Because the pigment is pure carbon, it won’t fade, react chemically, or change color over time. The main risk is mold growing in the gum arabic binder, especially in warm conditions. Adding a tiny pinch of clove oil or a single drop of thymol solution acts as a preservative. If the ink thickens from evaporation, add distilled water a few drops at a time and stir until it returns to a workable consistency.
Carbon particles will always settle over time, no matter how well you’ve ground them. Give the jar a good shake or stir before each use. This is normal and doesn’t mean anything has gone wrong.
Safety While Working With Soot
Fine carbon particles are a respiratory hazard. NIOSH classifies carbon black as a potential occupational carcinogen when polycyclic aromatic hydrocarbons (PAHs) are present, which they typically are in soot from incomplete combustion. Work outdoors or in a well-ventilated area when burning fuel and collecting soot. Wear a dust mask or respirator when handling dry soot powder, especially during grinding. The particles are extremely fine and light, easily becoming airborne with the slightest disturbance. Once the soot is mixed into liquid binder, the risk drops significantly since wet particles don’t go airborne.