Antique China Plates

I am responsible for liquidating my grandmothers estate and thought I'd check to see if anyone can give me any info on these gold leaf plates (see photos) before I sell them for almost nothing. I have been told by my grandmother these plates and 2 other similar plates (with different beehive marks) are worth a great deal, but I was unable to find the plates markings anywhere on the internet, particularly, the solid, black star mark with "Silesia" underneath the star.