Every watch collector has their own individual reason(s) as to the tipping point that caused them to shell-out his or her hard-earned money on a particular watch of choice. But the truly valuable timepieces, and not in the monetary sense, will probably include some sort of backstory related to watch lineage, watch movement, special edition status, limited edition status, materials used in manufacturing, or some other special "something" that sets it apart from just any other watch in your collection.
If someone has bothered to gaze upon your wrist, and offered a complimentary remark regarding the wrist-candy adorning your wrist, the least you can do is offer some additional tidbits of information regarding the how's and why's of such a beautiful work of art placed upon your wrist; if nothing else, to satiate the appetite of the inquiring mind.
The most notable conversation timepiece, of all-time within my collection, hands-down has got to be the Invicta Ruby / Diamond, Meteorite, COSC Pro Diver. First, this watch was easily the pink elephant in any room. Add 1 part rubies, 1 part sunshine, and a splash of diamonds around the crown, and you have an insane amount of bling. Every time I wore this watch, someone inquired about it. And there was a lot to talk about! Gemstones galore, rubies set around the bezel, diamonds in the crown, and a certified chronometer in an automatic dive watch. Then there's the meteorite dial, a dial material that isn't widely used within the industry.
My Invicta Ruby / Meteorite / Diamond COSC Pro Diver definitely personified the conversation starter timepiece. Unfortunately, I've long since sold this beauty, but have been fortunate to acquire additional timepieces to keep the conversation going.