Oops, it doesn't look like 'pendantics day' is a national day..

Other days

martini

Martini Day
pampering

Pampering Day
pumpkin

Pumpkin Day
bow tie

Bow Tie Day
frozen yogurt

Frozen Yogurt Day
kale

Kale Day
ruby

Ruby Day
boba

Boba Day
eat what you want

Eat What You Want Day
book

Book Day