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MINING
MINING AND MINING RESOURCES
Although there had been attempts for over a century to
establish small-scale mining in Jamaica, the present well-established mineral
industry of Jamaica only dates back to 1952 when the export of kiln dried
metallurgical bauxite ore was started. This was shortly followed by the
export of alumina. The birth of this new industry was the result of a successful
exploration and development programme. It was somewhat unusual in that
this development occurred in areas near to well-established population
centres with such infrastructure facilities as roads, railways and harbours.
All these, of course, had to be vastly improved to service the new industry.
Jamaica's mineral industry is mainly based on bauxite but it also includes
industrial minerals such as gypsum, marble, silica sand and clays, besides
a thriving sand and gravel industry.
The occurrence and distribution of the ferruginous terra rossa soils in
Jamaica was noted by the West Indian Geological Survey. An English surveyor,
J. C. Sawkins, stated in his Geological Survey Memoirs, published
in 1867, that the red earth was principally a mixture of iron and alumina.
However, it was not until 1942 that attention was given to the possible
economic significance of red earth, bauxite, as aluminium ore.
Legislation
Under the Minerals (Vesting) Law, Chapter 251, minerals are vested
in and subject to the control of the Government. The principal mining legislation
is the Mining Law Chapter 253, Law 41
of 1947. This was enacted after the Minerals (Vesting) Law and is supplemented
by the Mining Regulations 1947 as amended by the Mining (Amendment) Regulations.
The operation of quarries for many of the industrial minerals is controlled
by the Quarries Law of 1955. Development of petroleum resources is governed
by the Petroleum Production Law Chapter 292.
Bauxite and Alumina
Characteristics of the Ore: The bauxite deposits occur as solution.
cavity infillings within the members of the White Limestone Formation.
The depths of the deposits vary from over 30 metres (100 ft) to only a
few centimetres, but with an average depth of about 6 metres (20 feet).
Deposits less than 1.75 metres (5 ft) deep are usually not considered mineable.
A study of the composition of the bauxite deposits in different areas of
the island shows that there are distinct regional differences in the ore.
Companies: The commercial production of aluminium only began in the last
decade of the nineteenth century though the existence of the metal in certain
kinds of ore was known by scientists from the beginning of the century.
However, until World War II (19391945) greatly increased the demand
for aluminium, little attention was paid to the rich deposits of bauxite
outside Europe and the United States of America, including Jamaica where
geologists had noted the presence of the mineral as far back as 1896.
In 1942 a Jamaican businessman named Sir Alfred D'Costa had soil tests
done with a view to improving the fertility of his farm at Lydford in the
parish of St. Ann. On analysis, the soil proved to be highly aluminous
and through the exertions of Sir Alfred and the colonial authorities (Jamaica
then being a part of the British Empire) this fact was brought to the attention
of aluminium producers in the Allied countries. The mineral was vested
in the Crown in the expectation that it might be needed for the war effort.
In the event, Jamaican bauxite was not used during the war but three North
American companies Alcan, Reynolds and Kaiser came to Jamaica
to survey, acquire reserve lands and set up operations over the next few
years. Reynolds began exporting bauxite on June 5, 1952 from Ocho Rios
and Kaiser followed a year later from a south coast port. Alcan built a
processing plant near its mines at Kirkvine, Manchester, and in early 1953
began shipping alumina, the intermediate product between the ore and the
metal. Thus did the industry begin in Jamaica.
Production increased rapidly and by 1957 Jamaica had become the number
one bauxite producer in the world with nearly five million tones, almost
a quarter of all the bauxite mined in the world in that year. Alcan built
a second refinery at Ewarton in St. Catherine in 1959 but not until 1963
did a fourth company, Alcoa, begin mining in the island.
The production of alumina also increased, especially after the mid-1960s.
By 1968 Alcan had brought the capacity of its refineries to over one million
tones a year, and in 1969 a huge new plant was commissioned at Nain in
St. Elizabeth by Alpart. a consortium of Kaiser, Reynolds and another US
company, Anaconda. In 1971 Revere Copper and Brass opened the island's
fourth alumina plant at Maggotty, St. Elizabeth. Two years later Alcoa,
which had been shipping unprocessed bauxite since 1963, built the fifth
refinery at Halse Hall, Clarendon, near the ancestral home of Sir Thomas
de la Beche. one of the first of the great English geologists. As early
as 1827, de la Beche had remarked on Jamaica's 'red, marly soils' in the
first published notes on Jamaican geology.
By 1974 Jamaica had become the world's fourth largest producer and second
biggest exporter of alumina. No smelters were built in Jamaica, however,
and it is unlikely that any will be, largely because of two factors. The
first is that aluminium smelting or reduction requires massive electrical
energy; hence smelters are usually sited where there is hydropower, coal
or natural gas. Jamaica gets its energy from imported petroleum. The second
factor is that smelters are usually located in countries with a large market
for aluminium. The 1970s also brought other changes to Jamaica's position
in the aluminium industry. In 1971 Australia overtook it as the leading
producer of bauxite and that country now produces some 27 million tonnes
a year as against Jamaica's 11 million to 12 million tonnes. And in the
past few years, the West African country, Guinea, which has the world's
highest grade bauxite, has also drawn ahead of Jamaica. The island's share
of world bauxite output fell from 18.1% in 1974 to 9.0%in 1983.
Production in Jamaica rose by 45.1% to 2.2 million tonnes after a l.3%
fall in 1988. Earlier, 1981 had seen a -3.1% fall in bauxite but a 4.15
increase in alumina production. But between 1982 and 1984, during the world
recession, both fell considerably. By 1989 bauxite had begun to recover
with a 29.7% growth and alumina with a 45.1% growth.
The decline in the 1980s was said to be due to varied and complex issues
which included:
- world economic conditions
- lower growth rates for aluminium
- energy availability and costs
- the decline of North America as a major aluminium and alumina producer
in particular the Gulf Coast area
- take-or-pay contracts and consortia arrangements
- a surplus of alumina on the world market;
- differential pricing policies
During the 1970s there were important changes in the ownership of the
industry and in its contribution to the Jamaican economy. Although the
mineral had been owned by the State since colonial times, the companies
exploiting it were wholly-owned subsidiaries of North American-based aluminium
companies. Government purchased 51%, of Kaiser and Reynolds, 6% of Alcoa
and 7% of Alcan, and repurchased most of the ore reserve lands formerly
owned by the companies. In return, the companies were granted forty-year
mining leases. In 1974, following dramatic oil price rises, the Government
increased bauxite taxes by a Production Levy. The levy, in effect, indexes
the price of bauxite to the price at which the aluminium companies sell
aluminium ingots.
There are at present four bauxite and refining operations in Jamaica, Kaiser,
Alcan, Clarendon Alumina Production Limited and Alpart. Reynolds ceased
operations in April 1984 and Alcoa in February 1985. The Government also
set up new agencies to manage its enlarged interest in the industry. The
principal of these, the Jamaica Bauxite Institute, began operating in 1976
to monitor, regulate, conduct research and advise the Government on all
aspects of the industry.
Bauxite mining
Bauxite is mined by opencast methods using the most modern large
scale earth-moving equipment. The present emphasis is on blending to produce
a uniform grade ore, the use of lower grade bauxite, and the maximisation
of reserves. Mining is most commonly carried out using a benching method
requiring power shovels and draglines. The ore is transported from the
mine by a combination of rear-dump off-highway trucks, belt conveyors,
aerial tramways and railways. Ore for export is dried in rotary kilns to
reduce the moisture content, while that for local processing is used as
mined. About a half of the bauxite mined is shipped unprocessed to the
United States. The other half is processed on the island in the four alumina
refineries which have a combined capacity of some 2.7 million tonnes a
year. The alumina is exported mainly to Europe and North America.
Restoration
Jamaica is almost unique in world mining history in that, from
the inception, emphasis has been placed on the reclamation and rehabilitation
of the mined-out bauxite lands. This programme has been singularly successful,
in spite of the many problems involved. Further, the land between the pits
is usually included in the reclamation programme. Grass is the crop usually
planted on restored lands, Forest trees have also been established on restored
lands, though in much smaller acreages than those established in grass.
Orchard crops have also been planted.
INDUSTRIAL MINERALS
Gypsum
Gypsum occurs in the Port Royal Mountains of eastern St. Andrew where it
is mined by quarrying. It is used in Jamaica as a retarder for cement.
It is ground with cement in the proportion of approximately 1 part to 20
parts of cement. Another use is in the manufacture of plaster of Paris,
which is used to make ceiling tiles and plaster. Most of the gypsum produced
in Jamaica is exported to the USA, where it is made into plaster which
is then used to manufacture wallboards. It is also used as a fertiliser.
Silica Sand
Deposits of high grade quartz sand were discovered in the Black River area
by the Geological Survey Department in May 1958. They occur as irregular
patchy surface deposits in the gently undulating coastal plain. The purest
sand is used for the manufacture of flint glass for the container industry.
It is important that this sand contain iron oxide in order to produce a
colourless glass. The less pure sand is used as foundry sand, while the
finer fraction may be used as an abrasive in soap powder.
Clays
Deposits of clay occur in several areas of the island. The best is in the
Hodges area where it is associated with the silica sand there. The clay
shrinks considerably on drying. This presents problems in its utilisation.
At present small pockets of clay are used by the art potters and small
operators to make traditional Jamaican clay wares.
STRUCTURAL MINERALS
Cement
The manufacture of Portland cement was started under licence granted
in 1949. Limestone, the major raw material, is quarried at Long Mountain,
overlooking Kingston, and conveyed about 2.5 kilometres (1.7 miles) to
the plant where it is crushed and mixed with clay dredged from Kingston
Harbour or shale from nearby areas. Expansion of the plant has taken place
and now includes a belt conveyor system for the movement of raw materials
and the construction of a 900,000 tons per annum clinker plant. The growth
of the industry has paralleled the growth of the construction sector.
Marble
Occurrences of marble which is suitable for use as an ornamental
stone are on Serge Island, Mt. Auburn and adjacent areas of St. Thomas.
The colour varies from almost white, occurring at Bath in St. Thomas, to
black near Clydesdale and Tweedside. The coloration is due to accessory
minerals in the marble.
Limestone and Lime
Limestone is Jamica's most abundant mineral. The White Lime-stone provides
the rocks most frequently used. These vary from chalky to marly beds and
some contain flint nodules. Even the best of the hard limestone is usually
well fractured. Apart from being essential to the production of cement,
limestone is also used in building construction and as a fill in road construction.
In a few localities the limestone has a beautiful pink colour but in general
it is white.
Some horizons of the limestone are extremely pure and are used in the
manufacture of lime. This is a major raw material in the alumina industry.
Lime is also used in agriculture, sugar-refining, glass-manufacture and
building.
Sand and Gravel
Deposits of natural sand and gravel occur in St. Catherine,
St. Andrew, Westmoreland and St. Elizabeth. Elsewhere crushed and sized
limestone is used for the same purposes as sand and gravel.
METALS
Copper minerals occur in upper Clarendon, particularly in the Charing
Cross-Bellas Gate area, in the Rio Grande and Swift River districts in
Portland, and in the Port Royal Mountains of St. Andrew. Most of these
occurrences have been known since about 1869, but as yet no economic deposits
have been located although the Charing Cross and Standford Hill Mines in
Clarendon were operated briefly during the latter part of the last century
and between 1906 and 1909.
There are known occurrences of lead and zinc with some copper and arsenic
at Rock Castle in the Hope District of St. Andrew. This deposit was first
worked during the 18th century and abandoned. Mining was again resumed
about 1856 but was closed by about 1860. The remains of the adits, crushing
mill, and a concentration plant can still be seen.
Small high-grade deposits of iron ores occur on both slopes of the Blue
Mountain Range, and concentrations of magnetite-ilmenite sands occur, particularly
as beach placers. The largest is in the Alligator Pond area. Most of these
areas are currently under license and are being prospected.
Petroleum
Exploration for petroleum both on-shore and off-shore has been active recently.
The Windsor Spring near St. Ann's Bay and carbonaceous shales are perhaps
the best indication that petroleum could occur in Jamaica, but as yet too
few wells have been drilled for any firm decision on the probability of
finding petroleum here.
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