
I'd like to share a few of the techniques I use in my research. I sincerely believe knowledge is most powerful when shared and at least one internet behemoth illustrates my philosophy with ease and elegance; I am particularly fond of Google's online patent search as a powerful first step for many of my object research projects.
When I first look over an object, I hunt for clues that may include an artist or designer's signature, a company or retailer's mark, a registration number and/or a patent number. I recently purchased a set of silver "finger bowls" in Park City, Utah with teal enamel interiors. The pieces immediately put me in mind of the mid-century, silver plated, so-called "color glaze" tableware developed by American manufacturers such as Wallace, Oneida, Towle Silversmiths and Reed & Barton. These popular pieces were made in the spirit of higher-end enameled pieces crafted by a number of talented European silversmiths, including Georg Jensen of Denmark.
On the bottom of each finger bowl, I found the following marks: W & S BLACKINTON / FINE SILVERPLATE / SINCE 1865 / 50 / U.S. PAT. NO. 3,031,096. This mark provides several clues and a solid direction to follow.
I immediately went to Google's patent search, typed in the number and learned that Bruin T. Lipman of Meriden, CT filed a claim for this patent on 7 November 1961 for a "combination coaster and ash tray ... [with] the appearance of a silver dish, but the utility of a glass dish." The United States Patent Office granted his request on 24 April 1962 and thanks to this document (and Google's heroic efforts), I learned in seconds the name of the designer/inventor, the proper name and use of my new objects, their material make-up, geographic origins and date of conception. Follow this link to see for yourself!
At the risk of stating the obvious, a great deal of information for an initial inquiry don't you think?

I'll leave you with a final example. This pair of Art Deco era spiral or coil bookends of painted red wood and chrome-plated steel is stamped "REVERE / ROME, N.Y. / Pat. appl'd for" on base.
Here is a scan of the original patent:

Filed in1935 by Fred D. Farr for Revere Copper and Brass Company of Rome, NY., the "Pat. appl'd for" designation
makes this one of the earliest manufactured examples of
this clever design!
Update! I just learned of a new site that seems promising. Check out Pat2PDF to download a copy of a patent from the U.S. Patent and Trademark Office.