Here is an interesting one that is a first for me on a few levels. Two tone engraved case is all yellow gold on top with white sides and back. Case is clearly marked "Bulova" on one end with a shield and marked 10K Rolled Gold Plate on the back.. Outside 6 digit s/n, with no interior markings besides jeweler marks. Movement is double date stamped 1934 / 1935 and stamped "USA".
The 1934/35 Lone Eagle came in 6 variants , I believe this is one of them. Face matches ads for the white gold one, I find no ads for the two tone, but there is one other in the Db; this one has a suspect face Perhaps the 2 tone was available with either the yellow or white gold face.
Just like the other two tone referenced, this one has a 6 digit exterior s/n only.
1935 Lone Eagle