Some very interesting research by Cryptocard27 has unearthed a few facts that shed some light on this deck - a deck which has been a mystery as to its manufacturer/publisher. All we knew about the Sterling Card Company was that its address was 24 Vesey Street, NYC. CC27 has determined that American Phototype Company ["APC"] were at that address in the 1870's, likely at the time the deck was produced circa 1876. From the APC name, we might deduce that they were printers and likely the manufacturers of the Sterling deck. What we don't yet know is the relationship between APC and Sterling. Was it a trade name APC used? a subsidiary? just a customer? A final possibility is that by 1876 perhaps Sterling had purchased the business of APC and decided to try its hand at playing card manufacturing.
It should be noted that the Sterling deck is the only one known to have been produced by the company and only two copies are know to still exist. It is a fascinating deck in that the courts are quite different from any other courts we have seen and the indices were of a type only seen in cards manufactured by Eagle Card Co. [refer Hochman L5]. I have pictured the Spade Ace and Heart King below.