The M620 Stockholm is one of my many M600 pens. It bears a close resemblance to the Chicago (being more blue than the grey Chicago) and the marbelled pattern is the same as the Berlin and the Madrid. The M600 size is the most comfortable in my hand, though I would love if it was a bit heavier.
This nib is a bit of a mystery. It entered my collection with M620 Place de la Concorde, but being only 14K it is not the original nib for that pen. It has two chicks which makes it an older nib (new nibs only have one chick). It is a fine sized nib but writes like a modern extra fine.
The last of my 30 Robert Oster inks to be used. I have nothing to say about this bottle that I haven't said before. A good design.
A very slight red sheen on the swab over on the top right corner. An interesting shade.
The fine nib doesn't show this ink to its potential. A slight red sheen and shading in places. A nice green.