I got a dozen of these, I wonder if its a good idea i cleaned them. I guess they are silver. I hope they have some melt value.
The date on the coin is 1887. It is the 20th year of the Meiji era. The symbols that look like = and + are 2 and 10 respectively. Because the second digit of the date is 10, you multiply the first (2) and second (10) digits to get 20. The character before the = character is the symbol for "year" and the last characters after the + denotes the era. The Meiji era was from 1868 to 1912. The way to calculate dates requires knowing the era, subtracting one from the begining date and then add the number after the year character. In this case: 1868 - 1 + (2 x 10) = 1887. As for authenticity and value, I am not much help but there are online sites that can help you estimate a value and hopefully authenticity.
And its a terrible thing that you cleaned them, if real, you took away all value except for the pm value, if any
I really have no idea if they are, I got them for the silver content. I have some that has not been cleaned yet. I hope they are worth something. Cheers.
Based on that, the arabic numerals on the coin would seem to indicate a silver weight of 419 grains ( a bit over 27 grams) and a fineness of .900. Which sounds about right for the size comparison you gave. I estimate the total weight of the coin to be in the neighborhood of 30 grams, give or take, depending on what comprises the balance of the alloy (perhaps copper).
If genuine, they have a little more melt value than a worn common date Morgan or Peace dollar IF you can find a buyer that is intersted and well versed in foreign silver coins (cleaned or not).
The date is actually 1879. The inscription needs to be read in the opposite direction which would be "Meiji 12 year". Gary
If genuine (which can't be ascertained from a picture) it is .900 silver, weighing 26.96g, with a diameter of 38.6mm. Many of the fakes originating in China have the same 38.1mm diameter as the coins issued from 1887 on, which are the same weight, but infinitesimally thicker. I don't see any of the major calligraphy variations commonly spotted in Chinese fakes.
Although not a full yen, it'll give you an idea of what they look like when they've not been cleaned.