Vtg Matlack / MAC YEARLY Award Pin LOT 20+ Sterling Silver 1/5 10k Gold Balfour!

Description

PA Estate find
You get:
20+ Service pin backs etc from a former Matlack employee.
Included are:
(1) Bulldog MAC Pin
Safe Worker #: 2 Years
Safe Years #: 4, 6, 7, 8, 12, 13, 14, 16, 19, 21, 27
Years of Service: 11, 13, 14, 16, 19
3 cuff link buttons
5 tie tacks
2 Quality Award Pins
3 Stone Green pin
3 Stone Blue pin
12 loose backings
Now the good stuff:
(6) of the Safe Years Pins are marked on the back "STER" for Sterling Silver (YEARS, 6,7,8,12,13,14)
(4) of the Safe Years Pins are marked with 10k (YEARS 16,19,21,27). I can see the 10k along with other markings on these but can't make out what the other markings are.
The (2) with colored stones are marked CTO 1/5 10K. I do not know anything about the stones.
Everything is sold as is and as seen. If you have any questions please ask in advance. I am not a jewler and do not know much about the markings other then what I stated. I looks like many of these might be from Balfour.
No returns.Thanks for looking!