Iron tsuba signed "Hojusai Hirochika". This tsuba is very different from most of Hirochika work, it actually is so uncommon that it does not fall to any tsuba school I am familiar with. It might look a bit like Tanaka School.
Dragon and clouds are both made with gold nunome zogan. However gold alloys and amount of gold gold left on iron is different. Clouds are made with alloy with smaller amount of pure gold and nunome cuts are far away from each other. Dragon is made of higher quality gold and nunome cuts are very tight, so there is almost no space where iron is visible. Because of that inlay on dragon looks very different from the one on clouds.
There is one Hirochika tsuba in collection of MFA that usues same technique.