Vacheron Constantin is one of the big 3 Swiss watch brands that also include Patek Phillipe and Audemars Piguet. These are a tier above Rolex and Omega and they specifically trade on scarceness and exclusivity. You haven't heard of them because they advertise in very specific places to watch nerds and the very wealthy. Each watch can be like $30,000 to $50,000, or even $120,000 for small run products with unique complications.

There's more interesting brands like Moritz Grossman and Bovet that make even rarer pieces but fewer people have heard of them.