Sunday, March 15, 2020

PR122 purple magenta test

Go figure, there are many kind of magenta out there to pick from and I picked the wrong one. At least until now. In 2008 I visited Paris and had the chance to shop in the original Sennelier pigment store. That is a very old company that makes art pigments; the store was a three level building with narrow aisles, creaky staircases, and display cases all over showing off the pigment powders in jars and old equipment they used to use to make paint. They also had a box full of discounted paints that were a great bargain for a traveling artist.

Unfortunately one of the pigments I bought was Tyrian Rose- a natural pigment from shellfish used since ancient times also called Tyrian purple. Its chemical structure is a fluorescent molecule called rhodamine B which is quite toxic if ingested, the pigment is called PV1. By coincidence we also use this molecule in the laboratory- it will emit fluorescent magenta when excited by a laser which can be detected by the microscope or flow cytometer. As a paint pigment, it is considered terrible because it will easily fade in sunlight. That makes it a 'fugitive pigment'. I took it out of my palette at the beginning of this year, but I can tell that I used a lot of it, probably 10mL over the last 12 years.

To make a long story longer (hey we all have more time on our hands at the moment?), there is a new line of pigments called quinacridones that fill the magenta spectrum quite nicely. Quinacridone magenta (PR122) it almost identical to the old Tyrian rose, in the test example here you can see flamingo pinks, intense purples, and blazing yellow/oranges. Amazingly, when mixed with winsor green (PG7) it makes a neat lilac grey. There are some suspicions about the lightfastness of this pigment, Schmincke rates it only a 3 star our of 5, although handprint said it was about 7/8 on his scale.

I also bought PG36 (a yellow green), and PO62 a thick orange which are pretty cool too, I will post some new examples of them soon. In fact, on the bottom and left of this test I mixed PR122 with PO62, it creates a brilliant tomato colour.

6 x 6" watercolour, pad paper, 2020


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