A 75 ml glass bottle of clear golden liquid, labelled OIL COLOUR at the top with Mediums on the grey band, then ARTISTS' PAINTING MEDIUM and Medium Per Dipingere "Artists". The two lines that tell you what it does are printed straight underneath: Slows drying. Suitable for fine detail.

The first thing to get right is what this bottle is not. It looks almost exactly like the varnish bottle beside it — same moulded glass, same ribbed black cap, same Winsor & Newton band — but a varnish goes on top of a finished painting and a medium goes into wet paint on the palette. The one word that separates them is on the grey band: Mediums here, Varnishes there. Read that band before you pour.

Slowing the drying is the reason most painters buy it, and in this climate it matters more than the label can say. Oil colour skins over faster in a hot room, and a painter who wanted an hour of soft blending finds the passage already tacky and dragging. Mixed into the colour, this medium buys back that working time, which is what makes wet-in-wet blending, soft edges and gradual skin tones possible instead of a fight against the clock.

Suitable for fine detail is the second half of it. Stiff paint straight from the tube will not leave a fine brush cleanly — the line breaks, the tip splays, and a thin branch or an eyelash comes out as a smudge. A little medium loosens the flow without turning the colour to a wash, so the paint travels off the point of the brush and holds its edge.

The one rule to keep is fat over lean. A medium adds oil to the mixture, and oilier layers must sit above leaner ones or the upper film dries first and cracks as the paint below moves. In practice that means little or no medium in the underpainting and more of it in later layers, and it means adding it a few drops at a time rather than pouring it in.

This is our first oil-painting medium; the ox gall and masking fluid already on the site are watercolour helpers, and the two ranges are not interchangeable. Rs. 2,530 for the 75 ml bottle, Cash on Delivery across Pakistan. Keep it capped, away from heat and out of reach of children, and let an adult handle it.

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