True apostle spoons have one of Jesus's disciples at the end. Yours have the Madonna and Child at the end. They are called figural spoons.
The two JA/JS bear the mark of the sponsors' John Aldwinckle and James Slater of the London assay office area (leopard's head). The style G date letter is for 1882-83.
The duty mark for the monarch is the head of Queen Victoria. The lion passant guaranteeing sterling silver.
The other 11 bear the mark of the sponsor Henry Holland of the firm of Holland, Aldwinckle and Slater, the duty mark, the lion passant, the leopard's head but the style date letter A for 1876-77.
The set of gilded sterling silver (known as "silver gilt") would have an estimated retail value of $650-700 assuming good condition and depending in sale location.
Online auctions like eBay generally bring wholesale selling prices.
If you would like to sell close to estimated retail, some ideas are:
The internet has your largest audience of buyers. Place small ads on these sites or set up your own small store on these sites.
Etsy.com - small fees - 20 cents to list plus 3.5% final price.
Amazon Marketplace: http://services.amazon.com/content/sell-on-amazon.htm/ref=footer_soa?ld=AZFSSOA
Or your nearest CraigsList.com where you can list items for free.
These sites are excellent and more upscale but fees are higher. I only recommend them if you have several items to sell.
In general, a private seller to a dealer or at auction can expect 30-60% of estimated retail value.
Insurance replacement values are usually about 10% more than retail values.
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