I have a pair of diamond studs that I never take off. Other than that, essentials are all scarves for me. I mainly rotate between a black/blush/cream one, a black one and a white/grey one... I generally look for good quality ones on sale online eg asos or John Lewis.
Sunglasses: never sunny enough to need them Bracelets / necklaces: I have a lot, mainly silver, but wouldn't say they're essential. One that I got from notonthehighstreet that I particularly love - silver Moroccan buttons on a hammered loop and a really long chain... Rings: my favourite ones don't go with my engagement ring so I don't wear them much Belts: I'm too short, they make me look stumpy