Given the level of inflation we've experienced in the last 4 years, we don't need ANY coinage. It's all essentially worthless, most people won't even bend over to pickup a dime.
Honestly what Really should be brought back is the $500 and $1000 bill. It's just the government doesn't want us to have cash anymore
Yup. "What are you trying to hide when you carry that much cash?" Um, the outline of my wallet, which wouldn't need an inch-thick stack of 100s to carry the money for a car?
Actually, they did test Titanium in the past and may continue to when they do their Alternative Metals testing. From the US MINT report of: here's one such page of potential metals and an excerpt of their review...
Except for the toxicity (similar to mercury or arsenic). And the price per ounce (significantly higher than silver). But hey, stick it in a smoke detector and get a neutron source! I'm amused that they considered uranium. I guess there may be some Niven fans at the Mint, too.