https://en.numista.com/catalogue/pieces31487.html
Secondly, my coin has the characteristic K'ang (no horizontal bar upleft) of a "lohan coin", but not the same "xi (熙)", and "tong (通)".
My coin :
May I consider it as a standard "1 Cash - Kangxi Boo-chiowan" ?
Typical Kangxi cash - 1662-1722
Typical "lohan coin"
SECONDARY SERIES OF AD 1713: These coins, which are commonly called "Lohan Coins" differ in the way the bottom characher "K'ang" is drawn without the upright at the left. A myth about this variety claims they were cast from gilt bronze statues of Lohan's (attendants to Buddha), so each coin contains a trace of gold. No testing has found even a trace of gold in these, and there is nothing to support belief in this myth, which appears to originate in the mid-19th century. Burger, in his study of Ch'ing Dynasty cash, made a case for these coins being a special issue of AD 1713, to celebrate K'ang Hsi's 60th birthday.
Hartill lists these coins as having a rarity rating of 14, which means very common and somewhere in the $5.00 range. In my experience they are significantly scarcer than he suggests, and should in the $15 to $20 range. Schjoth lists these from three mints : Board of Revenue (see S-1419), Honan mint (see S-1434) and Hunan mint (see S-1435), although in the case of Honan and Hunan the mint marks are drawn slightly differently. When they become available we will add images of them.
reference : http://www.calgarycoin.com/reference/china/china8.htm
This is an example of an official Qing (Ch'ing) Dynasty minted coin, meant for general circulation, but which was immediately considered to have the powers of a charm. In the year 1713 AD, to celebrate the 60th birthday of Emperor Sheng Zu (Kang Xi), this special issue kang xi tong bao (康熙通宝) coin was cast with a bronze of a golden color. A 60th birthday is considered a major event in China. In honor of this milestone, the Chinese character xi (熙), which is located below the square hole, was written slightly differently. The character would normally have a vertical line at its left. Also, the part of the character normally written as (臣) has the center written as a (口) instead. Finally, the upper left part of the tong (通) character, located to the right of the square hole, has only one dot instead of the usual two.
Reference : http://primaltrek.com/charmfeatures.html