Difference between tzatziki and Indian mint dip (mint chutney?)
As far as I'm aware, the traditional Greek tzatziki doesn't generally include mint at all.

It's a cucumber dip that is made of yogurt and sometimes includes dill or mint as a flavoring:


  Tzatziki (Anglicized: /tsɑːtˈsiːki/ }; Greek: τζατζίκι [dzaˈdzici] or [dʒaˈdʒici]) is a Greek sauce served with grilled meats or as a dip. Tzatziki is made of strained yogurt (usually from sheep or goat milk) mixed with cucumbers, garlic, salt, olive oil, red wine vinegar, and sometimes dill. American versions may include lemon juice, mint, or parsley.


The main ingredients in all of the recipes I've looked at in researching this, are yogurt and cucumber and the flavorings are usually dill but occasionally either dill or mint. The Indian mint dip doesn't ever contain cucumber, as far as I know.

So, no I don't think they're similar products at all, mostly because tzatziki isn't "mint sauce" it's "cucumber sauce" that may happen to include mint.