L'Artisan Pastellier is french ink / calligraphy materials producers. They offer two lines of inks suitable for fountain pens: CALLIFOLIO (inks made for fountain pens, neutral PH and so on) and ENCRES CLASSIQUES (not all of them may have perfect properties however I've tried most of them and had no issues in my fountain pens).
L'Artisan Pastellier inks don't get much love or attention here. I understand this as they're not easily obtainable. You may buy them directly from the producer's on-line/stationery boutique.
I must admit I'm huge fan of Callifolio series. They have cool names and some trully unique colors. They're nor super-saturated but I like them this way.
There is thirty six colors in Callifolio line. Let's take a closer look at them.
Swabs on MONDI 90G paper
Gems (cut in PS from the photo made in intense sunlight)
Drops of ink on kitchen towel