Here is a mostly handwritten review of Organics Studio Boron which is a brown ink. The other brown inks I have are MB Toffee Brown, Sailor Do-you, and Visconti Brown/Sepia, both of which are somewhat harder than this ink. That in itself is not good or bad, just the way of this ink. How it appears can change quite a bit depending on the pen. In one pen it was lighter, but another it was darker.
Pictures taken with iPhone, so not really color corrected. I'll need to post the chromatics later as that's still drying. But there is a definite green dye there as well as the brown.
OS inks aren't being made anymore at this time, but Vanness Pen Shop appears to have a little of this particular ink in stock. There may be another retailer out there that also has some bottles. Anderson Pens has others of the OS inks, but not this one.