4. Sapphire. The blue gem is said to protect its wearer from misfortunes, accidents, unexpected and natural calamities, and mental tensions — and what could be more agonizing than watching a televised game of your favorite team against their number-one rival in your media room? If you can't afford loose sapphire gems, experiment with sapphire paint. This otherwise neutral man cave is enveloped in a lovely sapphire blue, bringing elegance and richness (and hopefully luck) to a masculine space.