Chop marks are post-mint marks put on coins (usually by merchants) to show they have been tested for authenticity (adequacy of silver content). Each merchant (or person) would have their own chop mark.
The 'sangii' mark could be related to a moth or flower that is so named, or it could be a company name or simply a chosen name by the merchant/individual who received the coin and warranted its value.
Good luck on attempting to find the specific "Who done it?" source for those marks.
Don...
PS: Trez, good to see you back; I await more of your spot-on COB IDs. Happy New Year.