1. Limestone as an Industrial Mineral
Kwaku Boakye Mineral Engineering Department and Bureau of Geology
New Mexico Institute of Mining and Technology February 9, 2007
I changed the title and the date (It still said a different month and 2006! Watch that when you re-use an old presentation to mske a new one

2. Outline Introduction Geologic description Distribution Production
Processing
Marketing
Uses

3. Introduction
Limestone and dolomite constitute a group of raw material commonly referred to as carbonate rock
In 2002, ~1.6 billion tons were produced in the United States (Freas et al, 2006).
71% of all stone quarried mined in the United State is carbonate rock
Find out if you are talking about metric tons, or tons, or tonnes, all correct terms, but they mean different things. You need to be exact about this because Ginger and Jim will want you to be. Please fix the date in the Freas citation , 200?

4. Geologic description Origin of limestone
Limestones of economic importance are biologically derived from seawater and originally deposited in relatively shallow marine environments
Environment of deposition and the organic community largely determine the geometry of a carbonate deposit
Environment of deposition is significant to the industrial minerals geologist because it determines the size, shape, and purity of the deposit
High-energy zones produce relatively pure limestones because clay impurities are removed by high currents
Are you sure about these environments of deposition being shallow? What about micrites? Aren’t they deep, cold water deposits that are really clean? Check on this please, add the other environments if it’s true

5. Mineralogy Limestone are sedimentary rocks
Chemical Composition of CaCO3
Similar in chemical composition as aragonite but different crystal structure
Aragonite is metastable and alters to
calcite in time
Siderite (FeCO3), Ankerite (Ca2MgFe(CO3)4) and Magnesite (MgCO3) are commonly found associated with limestone’s and dolomites

7. Limestone Limestone Sandstone

8. Chemical Properties
Chemical and Physical attributes are independent properties
Pure calcite in the form of poorly cemented chalk is not only unique in its low strength but also high absorption
Pure calcitic marble of the same chemical composition as chalk is relatively strong, unabsorptive, and unreactive
Chemical analysis is of upmost importance in stone used for chemical purpose, such as glass raw material, flux, or cement

9. Chemical properties are not so relevant for aggregates products
Chemical analysis are made to determine impurities
Impurities related with lime stone includes clay minerals, resistance minerals such as quartz, and organic material.
Most test are performed in accredited Laboratories
Many state surveys have files of chemical data obtained from quarry sampling and coring programs

10. Terminology used describe the purity of carbonates
High-calcium limestone:
greater than 95% CaCO3
High-magnesium dolomite:
greater than 42% MgCO3
High-purity carbonate:
greater than 95% combined CaCO3 and MgCO3

11. Physical Properties
Carbonates are similar in physical properties making it difficult to distinguish
Specific gravity, color, crystal form, hardness, etc are some of the physical properties
This properties are tested using testing procedures in ASTM and AASHO

12. Physical Properties of Calcite, Dolomite, and Aragonite.
Mineral
Chemical Composition
Physical Properties
Calcite
CaCO3
Hexagonal crystal system, commonly good rhombohedral cleavage. Mohs’ hardness, 3. Specific gravity, Commonly colorless or white but may be other colors because of impurities.
Dolomite
CaMg(CO3)2
Hexagonal crystal system, commonly good rhombohedral crystals with curved faces. Mohs’ hardness, 3.5 to 4. Specific gravity, 2.87, but common impurities such as iron can raise it to 2.95 or higher. Commonly white or pink.
Aragonite
Orthorhombic crystal system. Mohs’ hardness, 3.5 to 4. Specific gravity, 2.93B2.95. Commonly colorless, white, or yellow but may be other colors because of impurities.

13. Limestone pot hole

14. Distribution
Carbonate rocks are deposited from Precambrian to Holocene time (Parker, 1967)
Carbonate rock compose only about 0.25% of the volume of the earth crust (Parker, 1967)
Carbonate comprise of 15% of the worlds sedimentary rocks
Each carbonate deposit differ in their geologic characteristics
Highly-purity carbonate rock deposits are not overly abundant
Hawaii, Louisiana, Mississippi, New Hampshire and Rhode Island and all of Canadian Province are in abundance of pure limestone

15. Production Exploration Coring Rock Bitting Surface Sampling Mining
Open Pit
Underground

16. Processing
Processing varies with the end use of the product and targeted consuming industries
Site for processing depends on
Type of Mine
Haulage Distance
Surface Topography
Processing involves
Sawing
Crushing
Screening

17. Marketing Marking is influence by specification requirements
Specification differ from companies to companies even though they may produce the same product
Market price depends on the supplier ability to price the product on its value to customer but not the base on cost of production
Adding value involves strong commitment to research, development and corporate support from start of mining and followed by technical support

18. Uses
the manufacture of quicklime (calcium oxide) and slaked lime (calcium hydroxide)
cement and mortar
pulverized limestone is used as a soil conditioner to neutralize acid soil conditions
crushed for use as aggregate - the solid base for many roads
geological formations of limestone are among the best petroleum reservoirs
as a reagent in desulfurizations
glass making
toothpaste

19. Conclusion
Limestone and dolomite have been and continue to be one of the most important raw materials in the United States and the world
Limestone is a carbonate and sedimentary rock
Limestone of economic importance are biologically derived form seawater and accumulated in relatively shallow marine environment.
Market price depends on the supplier ability to price the product on its value to customer but not the base on cost of production
Demand of limestone and dolomite is expected to grow at an average annual rate of about 2.0% to 2.5%
In 2002, about 1.6 billion tone were produced in the United States (Freas et al, 200).

20. Reference
February 8th 2007
file:///I:/SME--ONLINE%20DIGITAL%20LIBRARY%20SURFACE%20MINING,%202ND%20EDITION.htm February 8th 2007
February 8th 2007
Kogel, E. J., Trivedi, C. N., Barker, M. J., and Krukowski, T. S., 2006, Industrial Minerals and Rock: Society for Mining, Metallurgy and Exploration, v.1, p , ISBN: /