I find these old brass surveyors/architects stencils so beautiful--paper thin, finely made, and shining rather like liquid gold in the light. I purchased a lot of them from a seller in England, and have broken them up into smaller thematic groups. These would have been used to annotate blueprints/architectural renderings, but as a lover of found language I like them as small, evocative signs of sorts, which could be interesting in all sorts contexts. These might be especially nice in a laboratory--or a kitchen!--where one is slicing and dicing things! Though of course a great gift for an architect, too. 

Very good condition. c. early 20th c.