Paint for OUTSIDE of stripped cast iron bathtub

[Caroly252]

My antique clawfoot tub is in perfect condition on the inside and needs no work on the inside of the tub. The OUTSIDE paint finish was cracked and had a few chips, so I had it professionally stripped with chemical strippers. It's now perfectly clean cast iron and I want to paint it myself. Which type of paint would be best and should I prime it first? I'd like to paint it a medium blue and will paint the clawfeet gold.