Is it important to know the numbers of the pigment?

Watercolor Painting & Sketching Group, Community, and Blog Forums Seeking Advice Is it important to know the numbers of the pigment?

  • Since I’m a rank beginner, and only have started using Winsor Newton paints, is it important to know the numbers? I see several artists listing them, but have no idea why to use them in addition to the name of the pigment.

    It’s a complex subject (what isn’t?).  If you are only using one brand of paint it isn’t as important to know the pigment number.  The issue, or at least one of the main issues, is that companies can give their pigment colors any name that they want.  For instance, Permanent Rose is usually the same color as Quinacridone Rose.  I believe Winsor Blue is usually called Phthalo Blue by other companies. Knowing the Pigment Index color might help you avoid buying a color you already have.

    However, there can still be confusion, because even a paint with the same pigment index number might be different because the amount of actual pigment used or a treatment – for instance raw sienna has the same index number as burnt sienna, but the ‘burning’ makes them totally different colors.  Many colors are made from the pigment PV19 but some are red and some are violet and there are several different shades in between.

    Some companies like to give their paints a fancy name.  If you see somthing like Very Violent Violet and see that the pigment index number is PV19, you can make a good guess that the color is one of the Quinacridone Violets and more reddish than blue.  You would also know that the color is probably transparent because PV19 usually is. With other colors, like PB29 (ultramarine blue), you could guess that it would be granulating because it usually (though not always) does.  If you see a paint named Ultramarine Blue with a different index number, you’ll know it won’t be the blue you might expect.

    Clear as mud? Lol. You can spend a lifetime figuring it all out.


    Yes to what Sandra said and I can tell you that learning about the numbers assisted me in not duplicating colors (unless I wanted to) when I  went to different brands.  Saved me $$ even in the Daniel Smith line, because some of their colors are simply too close unless you have ooodles of $$$.

    Follow Jane Blundell for her posts on pigments…. she is a good artist, not my style so that part doesn’t interest me much, but she is thorough about pigments and swatches.  Here is one on blues:

    Also, get to know  It is OVERWHELMING but won’t be if you pick a couple posts and begin to know them well… try reading as if you understand and you may begin to understand.  Here is a good place to start.  Frankly, I’ve nearly printed the entire site over time and am amazed at what it has taught me.  Suggestions:  (save this — it is the home page for watercolors.)  (print and save!  his color wheel, and a beginning to understand single pigments)   (explains a LOT about color)

    Serendipity.  I just came across this PDF – Pigment Comparison By Brand spreadsheet.  it isn’t comprehensive by any means, but has the most commonly used colors.

    Just to throw in another thing, I find I also learn about mixes by understanding the pigment numbers. Like PR is pigment red and Pbk is pigment black. So if I see Pbk in a pigment and it then claims to be semi transparent, I know it will be less transparent than I want because black is nearly always opaque. I try to have THE MOST transparent colors I can get and I find some colors are more transparent than others. It helps to understand what the letters mean so you can have some idea what a pigment mix is made of then you can make decisions if you like that mix. I may not like mixes that have black in them usually so I tend to look for a  mix that doesn’t have Pbk. Make sense??

    I refer to pigment number instead of paint names. Also, I think understanding pigments contributes to a better understanding of color mixing.

    Oh my gosh! My head is spinning with all this knowledge you all have thrown my way!! Wow!

    Until about a month ago, I was still using student paper and pigments. I bought Arches paper, but didn’t want to waste it until I got better at painting. It sat here for a very long time, and finally my oldest granddaughter said to just use one piece! So I bought three or four tubes of Windos Newton and tried it on one piece. OMGoodness what a huge difference. I’ve closed up all the student things and now to learn about the numbers etc.

    Thank you all so much for your information! This is the best site!

    Have fun – I think one of the reasons I like watercolor so much is that there is so much to learn about it.  You don’t have to – but you can really increase your repertoire if you do.

    Hi MMcBuck, I was much in your position only about two to three years ago, I knew enough to know I knew nothing! It was incredibly frustrating and I had no idea how to learn what I wanted to learn. I had books but I have a real problem learning from books, the info swims in front of me and doesn’t settle in my brain. I found reading Roz Stendahl’s site Rozwoundup ( and Jane Blundell’s site ( helped so much. Jane also has a great selection of swatches of nearly all professional brands, click on “tutorials & Resources in the upper right side to see them all (

    Although I warn you, Roz’s site is a rabbit hole of information and she advocates heavily for understanding color mixing. I get how important that is but I have learned enough that I now don’t pursue it ardently, I let it happen organically. If you want to read about my color choices and why go to my palette here. (

    While you’re building your palette, try to think of it as a split primary one until you build up enough colors that it won’t matter. A split primary is a warm and cool of each color, so a warm red would be an orange type and a cool red would be a quin red or a quin rose. Warm reds have yellow undertones and cool reds have blue undertones. Same for yellows, get a warm and cool of each, so a new gamboge would be a warm, and a lemon yellow would be cool, you can also just get a primary yellow like a pure yellow by Schmincke, one of my very favorite colors. Same for blues, a warm and a cool, you can even do this for the secondary colors. You can always google what is a warm blue, yellow, red, green etc to find out which color is which. Or, google the exact color you love, like “is phthalo blue warm or cool?”, you can even easier, use jane Blundell’s site again, here’s her link for cool blues… (

    Hope this helps! IF you have other questions, just ask, we’re all here to help and it’s always fun to get a gab session going about color!

    Oh and one other thing. In the spring there’ll be another new custom Schmincke palette by It’s a great deal and the colors should be much more in the split primary ideal than the current iteration that they are selling now. The new palette will be a little over $70ish dollars  US and may be something you think about if you’re wanting to try good paint. The current custom Schmincke palette they’re just finishing up with now is mostly opaqueish colors and many didn’t love the colors so I’d advise waiting for the new palette in the spring then thinking about it then.

    To add to Jennifer’s things to know about warm and cool colors, you’ll often see a (GS), (BS) or (RS) after a color’s name, like Prussian Blue (GS), Phthalo Green (BS) or Ultramarine Blue (RS).  Those stand for  Green Shade, Blue Shade, or Red Shade.  If you see these in a name, you’ll know this is a warmer or cooler version than the standard.  If it is a green or blue shade, it is a cooler version.  If it is a red shade it is warmer.  There are probably (YS) yellow shades out there too, but I don’t think I’ve ever seen one.  That would be warmer.

    Oh my… I can see I’ve opened a can of worms that need researching. 🙂 Thanks so much!!

    It’s so easy to do with watercolor because it is so complex!

    The amount of information buried in the articles of is amazing.   There is even a section of individual palettes of professional painters, which I am planning to eventually delve into, but of course after I have a better sense of the basic information.   I bought The Transparent Watercolor Wheel by Jim Kosvanec and am pretending I have the time to read it, just like I have time to paint. (!)  I am hoping my painting will improve with practice (that time thing again), but believe that learning how paints/pigments work is a big part of it.  Realizing that when I decide on a color for a painting, I want to know “will this stain?” “will this one be transparent”  “I don’t like my blue skies granular…what does this blue do?”  Wow, so humbling for a beginner.  I don’t even know all that I do not know.

    Shar, thats where knowledge begins, when you realize just how much you DON’T know. I was there about a year and a half ago, pulling out my hair, knowing I knew so little but not sure how to even ask the right questions. Keep plugging along, you WILL learn what you need to know.

Viewing 15 posts - 1 through 15 (of 15 total)
  • You must be logged in to reply to this topic.