have the distinctive "Diamond-O-I" marking just under the "7".
(Note: The "I" can appear as a dot in the middle of this mark like with this bottle, though on most it is a more or less distinctive "I".)Reading down through the narrative in Question #11, we find out that the number just to the right of the Diamond-O-I mark is the last two digits of the year the bottle was manufactured, which on this bottle is a "46".
If one looks closely at the thick glass in the base of the bottle, one can see that the glass is not quite perfectly colorless, but instead has a slight "straw" or washed out amber tint to the glass (picture of base below).
This is a result of using arsenic and/or selenium as the glass decolorizer.
The bottle also does not have a ground down surface on the top of the finish.