Tsuba signed "Iwamoto Munenaga" with NBTHK Tokubetsu Hozon Tosogu. Munenaga was active around 1825. Originally from Aizu in Iwashiro Province, later in life moved to Tokyo and became a student of Iwamoto Kanri. From him he received the right to sign Iwamoto.
This kozuka is decorated with crows and herons. To be precise NBTHK describe the motive as "Uro" which means crows and herons or black and white. It is written the same way as board game Go, played with black and white stones.
As far as I am aware this motive does not have a set interoperation. So here are few more interoperation ideas that I thought off. In Japan crow is a symbol of rebirth and rejuvenation, while heron is symbol of good luck. Therefore this tsuba might mean good luck on the new path of life? Two of the most legendary castles in Japan have those birds in their names. Himeji castle is called white heron, while Matsumoto is called a Crow Castle.
There are a lot of white spots on the lower part of the front of the tsuba. They become much more visible due to flash photography. In real life they are almost invisible as long as this tsuba is not observed in a strong light.
When I got this tsuba it was in much worse condition. After some care it looks way better. You can see the original condition on the NBTHK certificate.
Size: 73 mm x 69 mm
In custom made kiri box.