To promote Indonesian pearls, a series of integrated activities have been organized, among others, promotional exhibition both within the country and overseas, pearl auctions and trade fairs.
The Indonesian Government through the Ministry of trade encourage and support pearl businessmen to actively participate in international trade fairs in jewelry so as to penetrate the world market.
On top of those, the Indonesian Government has also established the Pearl Auction.
This annual event is organized jointly by the Government through the Ministry of Fishery and Marine Affairs in coordination with Asbumi (Indonesian Pearl Culture Association).
At production stage, the Indonesian Government through the Ministry of Fishery and Marine Affairs supports the pearling industries through research and development activities with regards to breeding of high quality oysters and improvement in pearling activities.
The Government also provides high quality feeds for spats to pearl farming business, on top of providing technical training on grafting and farming management.
As the guidelines for the activities to develop the pearling industries, the Government promulgated the Presidential Act No.32/1990 on The Management of Pearl Cultivation Areas which regulates spatial arrangements that specify boundaries to ensure the environmental conditions that are conducive for pearling industries.
Law no. 24/1992 on Spatial Management of Land Use specifies areas allocated for different purposes that includes areas for pearling activities.
The Government facilitated the establishment of Asbumi (Indonesian Pearl Culture Association) as the intermediary with the pearling business.
As an independent entity, the organization’s overall objective is to collectively improve the quality of Indonesian pearls in order to have a strengthened position in the world market.
Pearl cultivation operation can be divided into several phases as follows:
collection of healthy adult oysters, hatchery production, nursery rearing,
growing, grafting/nucleation, pearl formation and harvesting.
At each stage a number of different culture methods are used.
The method chosen depends upon the species cultured and the location or environment of the cultivation.
In Indonesia, pearl farmers have developed methods and techniques for Pinctada Maxima that have been adapted for specific characteristics of Indonesian tropical marine environmental conditions.
For the selection of good quality brood stock, namely the healthy and productive male and female oysters, before the 1990’s the main source for pearling activities was collection of adult wild oysters from the sea-beds.
However, after successful trial testing of hatchery techniques, as from early 1990’s Indonesian pearl farmers have relied on the hatchery production for pearling oysters.
Hatchery production allows selective breeding for desirable traits and assures a continual supply of juveniles.
During this hatchery phase, oysters’ larvae need micro alga (i.e. aquatic photosynthetic organism) as their food.
A balanced diet consisting of a number of species of micro-algae has been used in commercial hatcheries for pearl oysters from spawning until settlement.
In Indonesia, the pearl farmers’ needs for larval feeds are supplied by the Technical Service Units under the Ministry of Marine And Fisheries Affairs spread all over the pearl farming regions.
Good quality oysters generally will be ready to be nucleated at 21 to 24 months of age. From the time of nucleation, it takes approximately 18 months to two years for the pearl to grow to a desirable size, namely around 10 to 12 millimeters in diameter. (In extreme cases, the period may be lengthened up to 3.5 years after nucleation).
A medium quality pearl is estimated to have 1,000 layers of nacre on it, resulting in a nacre thickness of around 0.4 to 0.5 millimeters. A thickness of around 2 millimeters (nucleus plus nacre layers) after 2 years is just acceptable.
The daily deposition of nacre can vary from zero to seven layers per day. The main factors that determine the rate of deposition are, among others, the water temperature and the physiology of the individual oyster. The culture period necessary is also dependent on the size of the nucleus.
When the desirable size of pearl is achieved, harvest can be done. Harvest is done using two methods.
For oyster that has the potential to produce good quality pearl, the existing pearl will be taken out by another mean of operation and re-inserted directly with new nucleus.
The rest of the oysters will be killed and the pearl harvested.
Not all oysters harvested produce pearls.
A harvest is considered good when more than 55% oysters harvested are containing pearls.
For nearly 400 hundred year, pearls and pearl shells have been the most beautiful objects which have reached the outside world from the many islands of the Indonesian Archipelago.
DEVELOPMENT PEARL CULTIVATION IN INDONESIA
The trial tests of pearl culture in Indonesia started in Buton, Southeast Sulawesi as from 1921 by a group of Japanese experts led by Dr. M. Fujita, a leading researcher in pearl cultivation.
The venture was financed by the Mitsubishi Corporation from Japan. The test culture was using the Golden Pearl Oyster (Pinctada Maxima Jameson) collected from the Arafura Sea, specifically around the Aru Islands Group.
After seven years of trial and error, the test culture finally succeeded in producing rounded pearls with attractive colors and luster.
Thereafter, the sponsor, Mitsubishi Corporation, established the South Sea Pearl Corp. Ltd. (Nanyo Shinju Kabushiki Kaisha) which was operating the pearl farming business. The operation ended in 1941 due to the World War II.
In 1958, the trial test activities for pearl culture were resumed by Indonesian researchers and experts from the Indonesian Center for Marine Fishery.
The efforts were then continued by the Indonesian Research Center for Marine Fishery as from 1962.
The trial tests for pearl culture of Pinctada Margaritifera were conducted in the Gulf of Jakarta and in Semayang Island, Riau Islands Group.
The Research Center also tested the pearl culture of Pinctada Lentiginosa in the Kalabahi Gulf, Alor, East Nusa Tenggara.
The tests did not come out as ex- pected. As from 1960, pearl culture activities were started using wild Pinctada Maxima oysters collected from their natural habitat.
From 1990s onwards, pearl farming started using adult oysters reared from hatcheries.