i have never seen such coins before, so i searched the web and i found some info on these coins that i would like to share with you.
Thanks SM

"
COINAGE OF LANCHANG, BAR MONIES: Leech, Tiger Tongue, Boat This Thai kingdom flourished in what is now northeast Thailand and northwest Laos ca. 1353-1592. Its coinage consisted of rounded, rectangular bars called Lat, meaning "small money." The smooth, well-made base silver pieces with Elephant, Chakra, and a third stamp are called Leech Money due to their upturned ends, and were probably the kingdom's first coinage. There are three denominations, the small 18g, 37-40m being rare.
The capital of Lanchang was moved south to Vientaine ca. 1530 and Mitchiner dates the first Tiger Tongues to this period. These are of the same shape as Leech money with rows of rough bumps on the upper surface and sometimes stamped symbols across the center. After 1707 the kingdom split into Luang Prabang and Vientaine, and baser tiger tongues no doubt continued to be made well into the 19th century. As a whole the series is complex with variations in size, weight, shape, fineness, and markings."

Thanks again SM
