Hello Amena,
Yes, the Persian 84 is not a hallmark, it was applied by the maker. My source state it should be 875/000, you proved your box with the 84 mark is less than 500/000. You paid very little for it, and the intrinsic value is nearly 45% less than we thought it to be. Perhaps we better settle for the artistic value and the beauty of it or... just sell it without the relevant information 😏?
Anyway my shaker was made in 1961 by well known silversmith. I will keep you informed.
http://www.parvareshsilver.com/en/
FYI. According to my source Iranian silver hallmarks used 1967-circa 1979; country hallmark lion with scimitar in double frame for silver 900/000, single frame outline silver 875/000, metal purity mark-84 in Persian for 875 silver, maker's mark-silversmith's name, town mark
Domestic silver hallmarks period 1980-2010, due to embargoes and restrictions on trade, communication and information, no details have been found to support whether there was any hallmarking in this period, perhaps the old hallmarks of the Shah were suspended. Domestic hallmarks 2010- to date, a single stylized S with one square for silver 900/1000, with two squares silver 800/000.
Peter.
Source: Hallmark Research Institute volume II Asia, Middle East, Africa Danusia V. Niklewicz, Lindy L. Matula, William B. Whetstone, Iran page 133