If I had to guess - I would say that this is a mis-melt of black. Hey - it happens. You make a big batch of chili, but something happens and it comes out different. It's still good, but doesn't really hit the mark of chili, so you call it Festive Beef Surprise, and serve it anyway. Thus, a new favorite is born. As you may remember - vetro black - pulled very thin, was a dark blue - vs the Effetre black which is a dark purple.
Cobalt Night is a blue so dark it is as near to black as dammit is to swearing.
It would probably be excellent in applications like stringers and murrini, or shards. I bet it would rock in shards!
The rods only show the barest hint of blue right at an angle held up to very strong light - otherwise - they are convincingly black.
This is a gravity wave bead - horizontal stripes on a base, and melt while slowly rotating until the stripes travel all the way around the bead.
This will test the darkest glass!
This is a core of Cobalt Night - rolled in psyche frit and reduced. Not really what I was expecting ...
and some leaves ... which are pretty thin - and strongly illuminated.
This one, a close up from the top - developed this colour mark after mashing - couple of them did this.
Same piece - severely overexposed to show the detail.
Pieces strongly backlit.
I think this would function pretty well as an alternate to black, have good possibilities for blowing or shards, and I think that reaction with the psyche deserves further investigation. ;-)