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I adopt some innovative techniques of water management .I learn about UV resistant plastic lined
water harvesting systems silpolin, Geomemorian and nylon. The experts from CPCRI (Mr. Manoj .J .Samuval) extended me necessary
technical knowledge for designing and constructing . I constructed eight pond trapezoidal shaped water tank different sizes
2 lakh, 25000, 20,000, 15,000, 15,000, 10,000, 7,500 and 5,000 liter capacity . using for hatchery production and after
the post operation we are using same tank for mother oyster culture .
Creation of pearl's from Freash Water mussels
Pearl is one among the
perfect creation of nature. Pearl has a striking beauty, shininess,
colour and has the ability to keep its appearance intact, almost forever
There were many stories behind the formation of pearl. Indians believed that rainwater which trapped
inside the shell condense to form pearl. But now scientific truth about the formation of pearl came to light.
The most precious pearl in the world is believed to be ‘La Perry Graina’ which was the wedding
gift of Mary Dudark, daughter of king Henry eighth. It was obtained in 1500s from Panama sea. History says that the Kings used pearl as jewels. There was a huge
collection of pearl in the treasury of king of Hyderabad.
Pearl and coral are organic among the nine gemstones (navaratna)
namely ruby, pearl, coral, diamond, blue sapphire, yellow sapphire, emerald, cats eye and garnet. In this, pearl is formed
from shells in sea, river and ponds.
It is well worth noting, at this point, a little about the history of pearl culture which began in Japan. The first known attempts were in the 13th century,
where crude semi-round pearls were the result. Tatsuhei Mise (1880-1924) produced the first round cultured pearl before 1904.
Tokichi Nishikawa (1874-1909) became the first person to produce a round cultivated pearl from planned experiments using tiny
gold and silver nuclei. In
1890’s Kokkichi Mikki from Japan
and his colleagues invented the artificial preparation of pearl through natural method with human intervention. They kept
the secret for centuries by exchanging hereditarily. They used to wait patiently for years by keeping the images made of metal,
wood, clay and small statues of god inside the shell. Finally they could get a precious pearl from the shell. They developed
many new technologies on pearl culture that cost crores of rupees and later it spread to other countries also. Now most of
the countries are making and processing pearl for international market. Today, China
is contributing about 95% of the fresh water pearl. Even though it was developed in 1890s, the commercial production of pearl
was started only between 1960 and 1970. In 1990s China’s Fresh Water
Fisheries Research Centre (F.F.R.C) situated in Wuxi city
in Jiangasa province gave training to
100 trainees from 60 countries. Rice pearl from China having high value
is made from locally available shells called triangle sail mussels (Hyriposis cumingii) and wrinkle comb mussels (Cristaria
plicate). But ‘ Biwa pearls’ is made from fresh water shells called ‘Ikc chogai ‘ obtained from Biva
pond in Japan’s Shigu province.
Today pearl costing $2 billion is reaching the international market.
In India itself we are importing unprocessed pearl from China and Japan costing 100 crores and exporting as jewels
after processing and designing. China is exporting 100 ton pearl every
year and the neighboring countries like Bangladesh, Thailand, Philippines, Vietnam and Korea
have also started exporting fresh water pearl.
In India
scientist discovered 52 species fresh water mussels in the rivers and ponds. In 1989 a team under Dr. Janaki Raman from Central
Institute of Fresh Water Aquaculture (CIFA Bhuvaneswar) found out that out of 52 species, pearl could easily be produced from
3 types of mussels. Fortunately rivers and ponds of Kerala abundantly have these 3 species shells namely Lamellidens Marginalis,
L. Corrrianus and Parreysia Corrugata. This can be easily collected from a period of February to May end, ie., just before
the commencement of monsoon. After that this can be grown to proper maturity by putting in a farm pond for 4 months. The pond
selected can be up to 3meters deep. It is wise to avoid other living things that hinder the growth of the shells. Microorganisms,
Spirulina, Chorella, blue green algae, red algae (Chrsyophyceas), green algae (Chiorophyceae) and diatoms algae can be used
as food for the growth of these shells. Fertilizers can be used for the growth of the algae. For proper growth of shells ph
of the water should be maintained between 7 and 8 and temperature ranging from 15 to 250 C. September to October
is the ideal time to operate shells having size 8cm and above. Shells that overcome the operation should be grown by hanging
it 1m below the water level. Harvesting can be done from 12 to 18 months based on the food given. It is better to give a shade
over the pond in summer to reduce the temperature of water. About 80% of the shell mortality in natural habitat is due to the pollution
in rivers and hot summer. Many shells can’t survive in rivers due to seawater
intrusion during summer. Some of them will survive in the dykes and will
again flourish when rain comes.
There are 3 types of pearls available in international market today.
They are artificial pearl, natural pearl and design cultured pearl.
1. Artificial pearl
Artificial or imitation pearls are not pearls but pearl-like materials
that simply contain a rigid, round core or base and an outer pearly coating. This will lose its colour and appearance when
used for long time.
2. Natural pearl
When a foreign matter, sand, small stone or creatures are trapped between
the outer shell and the body or any other part, in order to avoid the unbearable pressure the nacre cells membrane will start
to grow on the foreign body. The aragonated secretion (a form of calcium carbonate) produced by the nacre cells will cover
the foreign body and later transformed in to pearl. The shape of the pearl will depend upon the foreign body trapped inside.
If it is trapped between the outer shell and mantle it will be shapeless and flat and have pearl cover only on one side. If
it is inside the flesh the pearl will be round. The pearl is a precious creation and blessing of nature.
3. Design cultured pearl.
When images designed by man is intentionally placed between the mantle
and outer cover of the shell, to avoid unbearable pressure nacre cells will starts growing around the foreign matter (cab).
Gradually the cab will transform in to pearl. In one way it is natural pearl only. Only thing is that it is not accidental
but due to human intervention. This design-cultured pearl will stay as the symbol of beauty forever. Only
upper part of the bead have pearl covering and when it covers completely the remaining part is cut from the outer shell. The
cab inside the removed part is removed and a special type of cement is filled in place. This type of pearl used in necklace
and earrings will certainly increase the beauty of the wearer. In
Bristol pearl one side
is flat. If the pearl have any other design instead of hemisphere it can be called as design pearl. The colour of the pearl
will depends on the food given and the type of mussel. Usually pearl made from fresh water shells are seen in pure white,
cream, pink, green, steel grey, gold rose and peacock blue. Pearl
has always been popular among the elite and common people due to its beauty and quality and longevity. Quoting in vedas says
that use of pearl will destroy all the evils and promote welfare.
Pearl industry in India
almost completely depends on the importing. Natural pearls are mainly imported from Bahrain. But fresh water pearls are imported from China
and Japan. Our pearl industry is mainly
based in Hyderabad. Actually pearl neither produced nor cultivated
here. Availability of eminent highly skilled laboures who make beautiful jewels from pearl is the reason for the international
popularity of Hyderabad. It is known that one third of the
gold produced worldwide is marked in India.
Today since the purchasing power of customers using gold have raised the gold merchants have stepped in to pearl marketing
and they are collecting and selling large quantities of pearl. It is sure that the demand for design-cultured pearl will keep
increasing in future.
The concerned departments should encourage the fresh water pearl culture as in the case of fresh water
fishing and prawn cultivation. It can be cultivated in an eco friendly and economical way along with other farming by using
materials like geo membrane, nylon and tarpaulin instead of concrete tanks in the farm. Central Institute of Fresh Water Aqua Culture (CIFA
in Bhuvaneswar) can guide people in protecting shells and cultivating pearl in a scientific way.
State fisheries department can cooperate with financial institutions and pearl cultivation development
agencies to promote pearl culture. Other institutions like NABARD can help the pearl processing units by giving financial
assistance. Government agencies can also arrange tours of interested farmers to other states for learning the farming techniques
existing there. The fresh water shells obtained from our rivers and ponds can be utilized for improving the living standards
of our farmers and hence increasing the wealth of the nation. This way let us try our level best to show our presence in the
international fresh water pearl market competing with China and Japan.
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