Which Pen to Use?

For formal uses (condolences and invitations, for example) you can never go wrong with black ink. Technically, dark blue is okay, too. But black always works. Just look at your wardrobe, if you need proof. For fun and informal correspondence, colored ink is great. We may obsess about stationery, but we're not snobs—you don't need a Mont Blanc pen. Just avoid ballpoint pens.

On envelopes, however, color just gets in the way. Blue and black ink are best because these colors don't hamper the automated mailing equipment at your post office.