Most sikins I have seen are of the less detailed type and little remaining enamal - especially those with three crowns. I have seen one with great detail and perfect enamal in a private collection but it seems to be very rare.
The 3 sikins I have are all more or less of the "simple" type and the one you mention for sure (although it also has gold inlay in the metalwork)
This might have to do that people of status (nobility and local authorities)were still allowed to wear a rencong by the end of the 19th century as it was a part of their status attire. These probably are the later types. The wearing of sikins was already prohibited by that time. According to a source high quality rencong and sikin were already a rare find by 1920 as there was little to no production so mainly heirlooms. Well this is at least my hypothesis based on the info above.
Originally Posted by Maurice
So the sikin with three golden crowns you bought on the last keris-fair this year in Bronbeek where we did meet, could be of the same age. That one also has that kind of less detailed crowns, like the " probably older" rencongs.