Hello! A couple years ago one of the first inks I bought was Organics Studio Potassium, but the bottle that arrived was a completely wrong color. After a brief pics exchange with the seller I got a refund and put the defective ink away (I'm a hoarder I physically cannot get rid of any ink but through writing). The recent activity from my fellow countryman Sansenri, together with my newly-rekindled interest in bluish and purplish hues prodded me to attempt to re-create the correct color of Potassium starting from my defective bottle.
This is the color I was starting from
As you can see it's totally off. It's got nothing of the charming purplish, delicately lavender hue it's supposed to have.
I needed a pretty purple... Rohrer & Klingner Cassia to the rescue!
I grabbed an eyedropper, a sample vial and some demineralized water, and started mixing away, noting the results on some scrap paper. In the end I was very satisfied with this result. One added bonus is that the mixed ink goes down a pretty purple, and dries towards the blue end of the gamut. I love that!
Cassia is extremely saturated, and the mixture potassium + cassia was the right hue but way too saturated and would not shade as much as I'd hoped, that's why I added so much water. The mixture sat in the vial for a few days and it is stable so far.