OP, I pawned all my jewellery around twelve years ago, to attend an overseas job interview and tack on two extra days. I was on benefits at the time, and desperate (and hadn't had an actual holiday for over fifteen years at the time).
There were rings, bracelets and necklaces, with an insurance replacement value of over 15 grand. I got £800. Of course, I could never afford to redeem the jewellery, and I regret it to this day - it still crosses my mind every few days.
It wasn't worth it.
I found a job later that year, but too late to get my jewellery back. There were things my parents had given me, one or two things from a great aunt. It still can make me cry. You are desperate, I really get that. But with hindsight, I would swap two days in Oslo in a heart beat.
Second hand jewellery is worth only the scrap value, at the end of the day - a fraction of either its cost or its worth. Pawnbrokers won't always lend on diamonds either, so you might not be able to get more than gold scrap. And with selling at auction, it takes time, and the seller's premium is hefty - plus you still won't necessarily get more than scrap.
Holidays aren't the be all and end all for children - we went away two or three times in my childhood and very early twenties. I have barely any memories from those times, other than that they happened - yet lots from childhood.
I really would wait it out and save for a caravan/Sun vouchers/do overtime etc