Rocks and Minerals - recommended book list

Hey guys, here's the start of a listing of great books on the topic of rocks, minerals, gemstones, fossils, geology, etc.

The Crystal Bible

by Judy Hall; Ann Marie Gallagher
ISBN: 1582972400
Beautifully illustrated, The Crystal Bible offers a comprehensive guide to crystals, their shapes, colors and applications. With informative descriptions and an easy-to-use format, it is an indispensable practical handbook for crystal lovers and users everywhere--both beginner and expert alike. The book's directory format and beautiful, full-color photos ensure that the crystals are easily identifiable. Descriptions, which accompany each entry, provide information on their appearance, worldwide distribution, attributes, actions and healing properties. Both major and lesser-known stones currently available are covered, including those only recently discovered. A comprehensive index cross-referencing crystals to applications, aliments and conditions makes this book a vital reference for all crystal users.

$21.99

The Crystal Bible, Volume 2

by Judy Hall
ISBN: 9781582977010

This updated edition of "The Crystal Bible" features information on 200 additional healing stones, and describes how crystals can be used to heal as well as their other valuable properties.

$21.99

The Crystal Bible, Volume 3

by Judy Hall
ISBN: 9781599636993

Overview N/A

$21.99

Nature Guide : Rocks and Minerals

by Ronald Louis Bonewitz
ISBN: 9780756690427

Published by Smithsonian, "Discover and explore the diverse world of rocks and minerals with more than 700 examples, Nature Guide Rocks and Minerals is the ideal companion for enthusiasts everywhere."

$14.95

Simon & Schuster's Guide to Rocks and Minerals

by Annibale Mottana; Rodolfo Crespi; Giuseppe Liborio
ISBN: 0671244175

"Practical, concise, and easy to use, Simon & Schuster's Guide to Rocks and Minerals contains everything that the rock and mineral enthusiast needs to know.  This field guide is divided into two large sections - one devoted to minerals and one to rocks, each prefaced by a comprehensive introduction that discusses formation, chemistry, and more.  All 377 entries, beautifully illustrated with color photographs and helpful visual symbols, provide descriptions and practical information about appearance, classification, rarity, crystal formation, mode of occurence, gravity of mineral, rock chemistry, modal classification fields, formational environments, grain sizes of rocks, and much more.  Whether you are a serious collector or an information-seeking amateur, this incomparably beautiful, authoritative guide will prove an invaluable reference"

NOTES:  This book is VERY complete, is goes in depth on all topics related to rocks and minerals.  It's a bit overkill for the beginner, but an AWESOME resource for an moderate to advanced rockhound.  Good stuff!!

$20.00

Smithsonian Rock and Gem

by Ronald Louis Bonewitz; Margaret Carruthers; Richard Efthim
ISBN: 0756633427

Starting with the Big Bang creation of the universe, Bonewitz (a geologist specializing in crystal chemistry with secondary training in archaeology per his New Age spiritually-oriented Web site) introduces types of rocks, minerals, gemstones, and fossils to novice collectors. The well-illustrated guide, published in conjunction with the Smithsonian Institution, includes a glossary but no further reading or resources.

What is a chakra? The basics.

Chakra Basics - What is a Chakra??

Here's some very basic information about Chakras.

a 'Chakra' is thought to be an energy point or node in the subtle body (a series of psycho-spiritual constituents of living beings, according to various esoteric, occult, and mystical teachings. According to such beliefs each subtle body corresponds to a subtle plane of existence, in a hierarchy or great chain of being that culminates in the physical form.).

Chakras are believed to be part of the subtle body, not the physical body, and as such, are the meeting points of the subtle (non-physical) energy channels called nadi.

'Nadi' are believed to be channels in the subtle body through which 'prana' (non physical life force) or vital energy moves.

Various scriptural texts present different numbers of chakras. It's believed that there are many chakras in the subtle human body, according to the tantric texts, but seven chakras are considered to be the most important ones.

I will go into more detail on chakra in another blog article ;) 

What exactly is a mineral??

What exactly is a Mineral??

Hey rockhounds!  At the request of a few members, I've quickly composed a brief description of what minerals are.  I hope it helps!

Minerals are typically defined as solid crystalline substances that are formed by natural (and usually inorganic) processes.  A mineral is characterized by homogenous phsyical properties, which means any two parts of the material will have the same properties.  These properties can vary with direction inside the crystal structure - for example a mineral might grow faster on one side than the other, or be harder on one side than the reverse - but this characteristic will be the same for any piece of that mineral.

Every mineral has a distinct chemical composition which can very within certain limits, but is always clearly defined.

Minerals also have distinct crystal structures.  What's that mean?  The atoms that make up the mineral are arranged in a regular and repeating three dimensional network or pattern.  No matter where a sample is taken from the crystal, the atomic arrangement will always be the same. 

Some minerals share the same atomic arrangement of atoms, with different types of atoms comprising the structure.  This is known as 'isotypism'.

Not all minerals are formed from inorganic processes, for example, some types of limestone - rocks that are essentially formed from calcite - come from animal and vegetable marine organism accumulation.  This calcite is usually considered a mineral because its usually identical with calcite formed by inorganic process and deformation and recrystalization usually occur in the formation of limestone.  Deformation and recrystalization are both considered inorganic processes.

Tips for Rock and Mineral Identification

Identifying Minerals

Minerals have certain mineral properties that are determined by their crystal structure and chemical composition.  These properties can assist in identifying many minerals.  Below is a brief overview of some key topics/terms relating to mineral identification.

COLOR:

Some minerals have a characteristic color;  Malachite has a distinct green, Azurite a blue, Sulfur is yellow, etc..  Some minerals occur in a variety of colors, for example, fluorite comes in almost every color.  These kind of minerals are better identified by properties other than just color.

Colors in minerals is caused by the absorption of refraction of light of particular wavelengths.  This can happen several different ways:
The presence of 'trace' elements - "foreign" atoms that are not part of the basic chemical makeup of the mineral in crystal structure.    As few as just three atoms per one million can absorb enough of the visible spectrums of light to give color to some minerals. 

Color can also be the result of the absense of an atom or ionic radical from a place that it would normally be in a crystal.  The structure of the mineral itself, without any defect or foreign element , may also cause color. 

Opal is composed of very small spheres of silica that diffract light. 

LUSTER:

"Luster" is the appearance of a mineral's surface in reflected light.  There are two broad 'types' of luster, metallic and non metallic.  Metallic luster is like an untarnished metal surface, like copper or gold.  These minerals are usually opaque (no light shines through).  Minerals with a non metallic luster are often transparent or translucent.  Vitreous describes the luster of a piece of broken glass.   A diamond's luster is called adamantine.  Resinous, pearly, greasy, silky and dull are also 'lusters'.. We'll talk more about each luster later.

STREAK:

Ok, so imagine this.  You have an unidentified mineral and an unglazed porceilain surface (like the bottom of a mug or plate, even).  You take your mineral and draw it across an unglazed porceilain surface.  A powder is created from the force of the friction of the two materials.   The color of this powder is considered your 'streak'.  A minerals streak is consistent, therefore it is a better diagnostic indicator than just color is, as color can vary.  Streak can help to distinguish between two easily confused minerals.  For example, iron oxide hematite has a red streak, while magnetite , another iron oxide, gives a black streak.
The streak of a mineral is consistent from specimen to specimen, as long as an unweathered surface is used/tested.  It is the same as the color of the powdered mineral.

CLEAVAGE:

The ability of a mineral to break along flat (planar) surfaces is called cleavage.  This happens in the crystal structure itself, where the forces that bond atoms together are the weakest.  Cleavage surfaces are usually smooth and reflect light evenly.  Cleavage is described by its direction relative to the orientation of the crystal, and by how easily it's produced.  If cleavage easily produces smooth, lustrous surfaces, it is called 'perfect cleavage'.  Distinct, imperfect, and difficult are less 'easy' kinds of cleavage.  Minerals can have different quality cleavages in different directions, some have no cleavage at all.

FRACTURE:

Some minerals break in directions other than those of the cleavage planes.  These breaks - or fractures - can help identify different minerals.  For example, fractures with jagged edges are often found in metals, while conchoidal (shell-like) are common in quartz.  Other terms used to described fracture are even (rough, but more or less flat), uneven (rough and irregular), and splintery (with partially seperated fibers).

TENACITY:

Gold, silver and copper are maleable and can be flattened without crumbling.  Sectile minerals can be cut smoothly with a knife; flexible minerals bend easily and stay bent when pressure is removed.  Ductile minerals can be drawn into a wire, brittle minerals are prone to breaking, and elastic minerals return to their original form after they are bent.

HARDNESS:

The relative ease or difficulty of a mineral to be scratched.  A harder mineral can scratch a softer one, but not vice versa.  Minerals are assigned a number between 1 and 10 on Moh's Scale.  Hardness differs from strength or 'toughness' - very hard minerals can be very brittle.  Most hydrous minerals - those that contain water molecules - are soft, as are phosphates, carbonates, sulfates, halides and most sulfides.   Anhydrous oxides - those without water molecules - and silicates, are rather hard. 

REFRACTIVE INDEX:

As light passes througha transparent or translucent mineral, it changes velocity and direction.   The extent of this change is measured by the refractive index:  the ratio of light's velocity in the air to its velocity in the crystal.  A high index causes dispersion of light into its component colors.  Refractive indices can be found using specialized liquids or inexpensive equipment.

FLUORESCENCE:

Some minerals exhibit fluorescence - they emit visible light of various colors when subjected to ultraviolet radiation.  Fluorescence is an imperfect indicator of a minerals identity because not all specimens of a mineral show fluorescence , even if they look identical and come from the same location.