A well-documented history regarding the doll can add a huge premium in terms of value. Always get the provenance in writing as part of the history of the doll.
Collecting vintage katsina dolls can become a lifelong obsession. I have been collecting and selling early Hopi dolls for over 25 years, and I have seen and learned much during that time span. Here are two pearls of wisdom:
If you are being offered multiple old dolls from a single collection, look to see if any of the dolls have identical color usage and carving style that would indicate the same carver’s hand. I have only seen dolls by the same carver in a supposed early original collection if they were done as a pair, such as representing snake dancers. Those trying to fake old dolls figure if one doll is valuable, then two or even three is even better; the greed factor reveals itself and helps undermine the forger.
Always make sure wear is consistent with human usage and not from mechanical aging, which is a common practice in making Old Style fakes, sandpaper being the most common tool.
Museums and documented early examples in books are great references for learning. When you’re ready to start collecting, buy from an ATADA (Antique Tribal Arts Dealer Association) dealer. The ATADA website is a great resource to find dealers who are very knowledgeable, love what they do and will guarantee what you buy. Wood and stone objects are the easiest types of materials for forgers to work with, so katsinam are a good target; though most forgers are rarely historically correct with materials and simply look for an easy mark.
"BUY WITH YOUR HEART, BUT DO SO ONLY AFTER YOU HAVE TAKEN THE TIME TO EDUCATE YOURSELF. NATIVE AMERICAN ART MAGAZINE IS A GOOD PLACE TO START.”
Zuni Many-colored Warrior of Zenith katsina, ca. 1930.