Full disclosure - I am not a jeweler or expert; just someone who has bought and sold some gold throughout the years. In my experience, jewelry stores, gold buyers, etc will only pay 70% of melt, max, and probably closer to 50-60%. To get more than that you'd need to sell directly to someone interested in the piece for personal use (eBay). The middleman has to get their cut! But melt (or a little less) is a good starting place to negotiate, and it will let them know you know what you're talking about so they won't try to screw you too bad.
Here is the calculation:
Current gold price (by ounce) times gold content (ie: 22K) divided by 24. This gives you the melt value for an ounce of gold at the gold content you're dealing with (ie: 22K, 14K). Then divide by 31. This gives you the price per gram, then multiply by the gram weight of the piece.
Today gold is at $1259 an ounce so..... 1259*22/24 = $1154.08 (value of an ounce of 22K gold). 1154.08/31 = 37.23 (value of a gram of 22k gold). $37.23 * 4.28 (weight of your piece) = $159.34 (today's gold melt value of your piece). 159.34 * .7 = 111.54. So $111 would be what I would aim for if using a gold buying place, which is easier than finding a direct buyer. Depending on how quickly I wanted to do this, I may accept as low as $80 (50% of melt). It seems some of these places have strict calculations they use and won't go higher than, say, 50-60%. Someone in their own business would have a little more leeway.
Here is an example of a 14K ring of 5 grams. 1259*14/24 = 734.42 734.42/31 = 23.69 23.69*5gr = 118.45 melt. So about $60 (50% of melt) to $83 (70% of melt) is what I would expect to be offered for it.
Also, be aware, some places deal in pennyweight versus grams. A pennyweight is 1.555 grams. So your piece is 2.75 pennyweights. If they talk about pennyweight, don't let it throw you. The final dollars should come out the same. I just go with my gram calculations and don't try to convert to pennyweight, so confusing!
Anyone in the business, or anyone who has consistently been able to get more than 70% (other than eBay), I'd love to hear about it.
Good luck!