This is a button hook dating between the late 1800s and early 1900s. Button hooks made their first appearance in 17th century but they entered more common usage during the 19th century. 

A button hook was an instrument to facilitate the buttoning of shoes, gloves, and the like.

Impossibe small buttons adorned all kinds of clothing during the Victorian period and having a button hook handy could make life much easier.

Most people, rich or poor, would have owned a button hook but the wealthier classes might have owned hooks made of Sterling silver like this one, while the lower class versions would have been constructed of wood or mixed metal.