Watercolour has no white paint worth using. The white in a watercolour painting is the paper itself, which means every highlight has to be planned and painted around — and one careless wash across a branch, a wave crest or a face and it is gone for good. Masking fluid is how that problem is solved: you paint it over the areas that must stay white, wash freely over the top, then rub the dried film off and the bare paper is still there.

The label states the job in one line and, unusually, our photographs prove it. Under the Mont Marte Premium block it reads Masking Fluid, then Fluide de Masquage and Máscara Líquida, and beneath that Keeps watercolour paper white with the same line in French and Spanish. The photographs show exactly that: a tree with bare white branches standing against an orange and pink sunset wash, and a second against a blue one. Nobody painted those branches — the wash simply could not reach them.

It comes as a 120 mL glass jar in a printed box, and the fluid reads pale cream through the glass rather than colourless. That tint is useful, not a fault: you need to see where you have already masked. One of our photographs shows it decanted into a small dish beside the brush, which is how it is actually used — you do not dip into the jar, because masking fluid ruins a brush left sitting in it.

Two things worth knowing before you buy. First, protect the brush: wet it with soapy water and wipe it before loading, and wash it the moment you stop. An old or cheap brush is the traditional choice for this job for good reason. Second, do not leave it on the paper for weeks — the longer a masked area sits, the harder the film is to lift cleanly, and on soft paper it can take fibres with it. Rub it off with a finger or a rubber cement pickup once the painting is fully dry.

On price it is the dearest liquid on our shelf. Rs. 4,500 for 120 mL is Rs. 37.50 per millilitre, just above the Rs. 36.67 of our Winsor & Newton Galeria matt varnish and far above the Mont Marte acrylic mediums at Rs. 5 to Rs. 9. It is used in small amounts on small areas, which is what makes that rate liveable — but it is a specialist purchase and not something to buy speculatively.

It suits watercolour and mixed-media painters from about 12 years up. The Safencia price is Rs. 4,500 with Cash on Delivery across Pakistan. Stock, your city, and delivery charges are confirmed on WhatsApp before dispatch.

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