I have only seen one example of this brand of Swedish tanged, bevel-edged chisel so far.
It has a beech handle with no label, a dimpled black enameled steel hoop on the top, and a brass ferrule with medium vertical knurlings. From it’s overall appearance, I would guess that it was made in the 1950s.
The logo makes me grin a little, probably because of the rather odd pairing of a fish and a diamond. The fact that the logo appears twice on the back of the blade is a bonus. The fish may have been an attempt to leverage off the recognition and popularity of the Berg shark. The back of the blade is also stamped “MADE IN SWEDEN”.
The front of the blade is marked only in inches — in this case 5/8″.