This thread has been of interest to me since I had purchased a "lot" of inks this summer & among them were two bottles of Rubinato ink, one with the cork top & the other in one of the more traditional Rubinato short round, with 8 sided bottle & a brass lid. Both bottles carried the G. Gnocchi reproduced labels; the larger one similar to the ink shown in the first post here.
After searching the forums, per BiggieD's suggestion, I found a post from 05 September 2009 by FPN Member, Nodge offering two bottles of the same Rubinato ink I have, "Inchiostro ANTRACENE," which identical to the label on my bottle, (probably the 75 ml, not the smallest bottle) whose similarity to the bottle discussed in this thread, caught my eye.
(I also found BiggieD's post from 04 November 2011 in "Gifted inks," when he mentions his lamented bottle discarded in the move.) I can only say that there are probably bottles of the brown ink out there, somewhere, mine were from an Ebay listing in which the owners were "moving house" & selling all manner of things. I bought 30 bottles of ink to acquire three of the bottles sold, of which I have only used one for pens & the other two for display,( the Rubinato bottle with the brass lid is marked "Calligrafico,"so clearly not intended for a "filled" pen.)