TIFFANY & Co. UNION PACIFIC Service Pin w/ 3 Blue Stones #925

This is a collectable Tiffany Union Pacific lapel pin with the Union Pacific logo, five stars across the top, and 3 blue stones across the bottom and hallmarked Tiffany & Co. 925 on the back. It is in excellent condition.
I do not have all the details about this pin, but have culled the following information from other sources. Some sources have identified it as either a 25-year or a 30-year service pin, either gold or gold-plated sterling silver (uncertain), and the three blue stones are likely to be either sapphires or topaz (one sold in an estate auction identified as sapphires, while another was sold identified as topaz. Again, let me be clear that I am not certain about the these details.
I can say that it is a beautiful lapel pin, the photos do not do it justice, and it is definitely marked as Tiffany and Co.
I'm sure this would make a great addition to your collection!