Earth & Mineral Pigments + Oil
You can use linseed oil or walnut--we recommend walnut oil because it affects the color the least whereas linseed oil can turn your pigments slightly yellow. The walnut will take longer to dry than the linseed, but if you are working with oil you’re likely familiar with a long drying time anyway. After you have gone through the steps above to crush and your pigment to a powder, combine the pigment with oil using a muller on tempered glass or some flat clean surface. You can also just use a palette knife, but a muller can work the pigment into the oil to create a stronger and more unified suspension. Work the pigment into the oil in a figure eight pattern, adding more oil or pigment until you reach your desired consistency. The paint should stand up on its own and hold its shape without sinking into a puddle.