is a small art materials company that makes a variety of high quality art supplies. They don't try to be a one-stop shop, but instead concentrate on the niche of the best, most difficult to find stuff. They make a variety of oil painting mediums, such as Maroger's, Roberson's, copal, wax medium, a glazing medium, and underpainting medium. They also provide materials for making mediums, such as oil of spike, Canada balsam, clove oil, and black oil. They have a line of oil paint, ground in linseed oil, that is at least as good as any other brand I've tried. Some of their prices are high, but not unreasonable when you consider that they are, in fact, using the best materials available.
Here are a few of the products from their catalog that I've tried.
Lead primer in black oil: this is a perfect lead white primer. It doesn't dry to a brilliant white, but rather to a pleasant warm tone.
Black oil: This is linseed oil cooked with lead. Black oil is slippery and dries very quickly; it is an excellent component in painting mediums.
Glazing medium: Use this by spreading a thin layer onto the dried surface of your painting, then applying paint thinly into it. Thick and slippery.
Special aged oil: This is a particular grade of linseed oil, excellent for grinding your own paint and for making egg-oil emulsions.
Oil paint: as I said, I have not encountered anything better. It has the kind of consistency you get with freshly ground, homemade oil paint. It is expensive, but note that their standard tube is 50 ml while most of their competitors use 40 ml tubes, so it's not quite as costly as it looks.
Oil of spike: This is a solvent, similar to spirits of turpentine. Compared to turps, it evaporates more slowly and is more slippery. It has a strong, pleasant smell.
Maroger's medium: This is black oil and thick mastic varnish. You can buy a pre-made version or one that you mix up yourself (it takes 20 minutes to gel). Added in very small quantities to paint, Maroger's noticeably improves the handling quality of oil paint.
The company also hosts the Cennini Forum, a place where painting topics are discussed with a knowledgeable and lively group of artists. The moderator is Rob Howard, whose sometimes acerbic style of forum management does not agree with everyone. If you stick around, you'll learn lots about painting and painting materials.