Molly's Brown Apron

Molly wears this brown apron when Mr. Gibson tells her she is going to visit the Hamleys, and when Mr. Preston visits. I think it is the exact same pattern as the green checked apron.

Note the bib and waistband:

and the back closure:

All I know about the material is that it is brown. Cotton? Linen? Something else? I don't know! :-) You decide! :-)
I recommend using In Timely Fashion's apron pattern for this as well!