Another thought--this might be a stock photo, and you would not be receiving the item in the photo, even if you win the auction. Akoya pearls, as you may have already read here, are formed over a mother of pearl bead, as opposed to most freshwater pearls, which form over a small piece of tissue (generally). The nacre on the poorer quality Akoya is thin, and this affects the wearability greatly. Good Akoya pearls are going to cost you a lot more than $50, that's the bottom line.
How can I tell the difference between akoya and something else?
It is not always easy to tell the difference, some faux pearls are shiny and round like Akoya. Just keep reading, and looking at the photos here, check out pearls in your local stores. Looking at pearls on ebay is ok also, there are a few trustworthy ebay sellers mentioned in the posts here on the forum.
My choice, for a wearable strand of pearls that will last a lifetime would be to go with freshwater, however. The prices are very reasonable for high quality, and basically an all nacre pearl. Do yourself a service and look at the freshwater strands offered by online sellers that post here. Most of us have made many purchases from them, both akoya and freshwater, and are totally satisfied by their fab customer service, generous return policies and gorgeous pearls at great prices!
Soon your eye will learn to discriminate between------Good luck!