You could build up an entire library out of the numerous books and magazines about rockhounding in Utah (and rockhounding in general). I’ve compiled a list below. My goal is to eventually include a review and a link to purchase on Amazon for each one.
Gem Trails of Utah
-James R. Mitchell
There’s a good chance that even the noobs in the utah rockhounding scene have come across this book at one point or another. Although it was published in 2007, it is still one of the greatest resources for this area. Most of the pictures are black and white (not very helpful obviously), but there is a section in the middle with several color pictures of specimens he has found in the areas mentioned in the book.
Rockhounding Utah
-William A. Kappele
Rockhounding Utah, 2nd 
-William A. Kappele
Utah’s Gems 
-Richard J. Dalrymple
Rocks, Gems, and Minerals of the Rocky Mountains 
-Garret Romaine
Like it says in the introduction, this guide was designed with beginners in mind. For each rock, fossil, mineral, and gem listed in this reference you will learn the chemical formula, group/family, mineralogy, Mohs scale, specific gravity, key test(s), likely locale(s), and a short description. I enjoyed this book because it focuses mainly on the specimens you will find in the Rocky Mountains of North America of which most are found right here in Utah. It was written by a rockhound which I always like to see so I would definitely give it a thumbs up.
Rocks, Gems, and Minerals of the Southwest 
-Garret Romaine
Agates: Inside Out 
-Karen A. Brzys
This is one of my favorite rockhounding books. Out of all of the books on my shelf, this is probably the one that is worn out the most. This book is the second of a two part series and seeks to help the reader “think like an agate.” As you may know, the various types of agate are numerous and I am sure that thousands of books could be written about the subject. What I like most about this book is that it is comprehensive and covers not only the definition of an agate as well as locations of agates all over the world, but it also helps us rockhounds in our search to actually go out and find these amazing specimens including tips on how to clean and assess the value of your finds. Also, the pictures are STUNNING!
Gem and Stone: Jewels of Earth, Sea, and Sky
-Jen Altman
I have to be honest on this one and say that I bought this book mostly because of the pretty pictures. What this book does contain though is an alphabetical list of to top 50 gems and minerals from the “earth, sea, and sky,” everything from Agate to Turquoise. Each page will explain some historical uses for each jewel as well as common locations for where each can be found. One can also learn which gem is associated with his or her birth month and Zodiac sign as well as some traditional metaphysical and therapeutic uses for each of these stones.
A Field Guide to Rock and Minerals
-Frederick H. Pough
Penguin Dictionary of Geology
-Philip Kearey
Dictionary of Geology and Mineralogy
-McGraw-Hill
Smithsonian Handbooks: Rocks and Minerals
-Chris Pellant
Collecting Rocks, Gems, and Minerals: Identification, Values, and Lapidary Uses
-Patti Polk
Simon & Schuster’s Guide to Rocks and Minerals
-Martin Prinz
National Audubon Society Field Guide to North American Rocks and Minerals
-National Audubon Society
National Geographic Pocket Guide to Rocks and Minerals of North America
-Sarah Garlick
I love these little pocket guides that you can just put in your jacket pocket and browse through whenever you have a free minute or two. This book is broken up into four sections: minerals, rocks, fossils, and structures & landforms. On each page you will learn the chemical formula, class/type, hardness, streak, texture, composition, and location of each reference as well as a fun fact or two. At the bottom will be a short description that could include anything from how it is formed to common uses.
Pocket Genius: Rocks and Minerals
-DK Publishing
Geodes: Nature’s Treasures
-Brad Lee Cross
The Rockhound’s Handbook
-James R. Mitchell
Modern Rockhounding and Prospecting Handbook
-Garret Romaine
The Illustrated Guide to Rocks and Minerals
-John Farndon
Rock and Gem
-Ronald L. Bonewitz
You know if it is the Smithsonian they aren’t going to be rolling out any rockhounding books that are sub par. This book is anything but. It contains hundreds upon hundred of rocks, minerals, and fossils. If you are looking for the most comprehensive book on this subject, look no further. The information is extensive, it is well organized, the pictures are abundant, and it is just an all around tremendous resource. It is almost like taking all of the other books on this page and combining them together into one. Like it says on the front cover: the definitive guide.
Nature Guide: Rocks and Minerals
-Ronald L. Bonewitz
This book is like the younger sibling of the Smithsonian Rock and Gem. It is also about half the size. The different minerals and rocks are split into their respective categories with each page detailing a particular specimen. Each description includes a profile, list of variants, and high definition picture. The introduction is a good place to start (obviously) with sections on identifying minerals, crystal habits/systems, and organization/storage/cleaning.
Rock and Gem Magazine
-Beckett Media LLC