Ancient Forests

By F.J.Daniels & R.D. Dayvault
Western Colorado Publishing Company
2024 Freedom Court, Grand Junction
Co 81503-9522
U.S.A
970.242.5255
Price: US$89.95 + US$16.75 for shipping
publisher@westerncoloradopublishing.com

Book Review by Arthur Main, Canberra, Australia

The book illustrates American specimens with some 80 pages devoted to choice pieces from American University museums. Nevertheless a range of countries are included with Argentina, Zimbabwe, Indonesia and Australia well represented.

In the introduction to this book the authors state that the emphasis is on beauty and as such many bland specimens were dismissed though they would be of great interest to palaeobotanists.

“Collectors quickly learn that petrified wood usually comes in two general forms. Either it looks like wood on the outside and shows detailed preservation of cellular structure on the inside, or it looks like wood on the outside but exhibits various textures on the inside, none of which resemble wood.”

From the last statement the authors deal with the complex chemical processes involved in the formation of opal and agate. Indeed, many photos were those of agate; but they had a wood-like skin. The many microphotographs show the cell structures of a wide range of trees, both hardwood and softwood, most of which are still living. So how did some trees become petrified?

Like all natural gems there are an awful lot of ‘ifs’. The range of minerals associated with petrification is also astonishing. Over 40 minerals have been identified. Apart from hydrous silica (opaline) and microcrystalline quartz (chalcedony), iron may be present as oxides, hydroxides and sulphides; likewise for copper. The range of actual elements also includes uranium.

This is a highly specialized book dealing in great depth with an often ignored gem material. It brings together components of botany, palaeobotany, geology and mineralogy. But above all: “Beauty is more wonderful when rare and especially so in the presence of perfection.”