Hello, I agree with the food idea. The neck has thick enough glass for a cork without an applied ring. The dot cone on the bottom is a vent hole. The drilled vent was cleaned with a pointed tool and wire so it became a cone on the glass. Later these cones became centering devices for snap-case bottle holders for neck tooling vs empontilling.
Nice glass bottle I like the concave corner edges on the bottle. Congratulations.
RED Matthews
I have one of these myself, have always liked it even though it is just a food jar . I was told it held olives , it could have held something else though .
A capers it is... The color... the length... the shape...
I found one a couple years ago similar to yours, but mine was embossed with "Guldens" the forerunner of Guldens mustard I have been told. Nice looking bottle.