An Indispensable Resource
"Gems", originally by Robert Webster but latterly edited by Peter Read is one of those volumes that have such a wealth of information on their topic that they are a "must have" for anyone with any pretensions to scholarship.
Robert Webster was originally a Pawn Broker whilst Peter Read is from a more academic background. The result is that the volume starts from a deeply practical base yet misses none of the more theoretical aspects of the subject.
If you are at all interested in gems, gemmology or jewellery, whether as a buyer, a seller or just an admirer, a copy of this book should be on your bookshelf. Early editions, whilst dated and obviously lacking the information on new discoveries in later editions, still read well and if due allowance is made for time, are well worth having, should the cost of a new copy give you pause.
The best advice I can give the budding Gemmologist is "Invest, you will not regret it"