Rare Natural Pearls

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This is my collection of rare natural pearls.

These pearls were harvested, under an aquaculture license in the late 80's and early 90's, experimenting with several species and techniques while analyzing the viability for large scale rearing and production of marine invertibrates on Meares Island, in the province of British Columbia, near Tofino.

California Mussels (Mytilus californicianus) grow in huge clusters along exposed rocky outcroppings of the North Pacific Ocean, ranging from Baja California to Alaska.

In the northern regions, California mussels are not a harvested as a food source. They have a tendency to uptake and retain for long periods, dangerous concentrations of organisms, known as Paralytic Shellfish Poisoning (PSP), or Red Tide. Gonyaulax spinifera, is a genus of dinoflagellate (single-celled aquatic organism) that inhabit fresh, saline, or brackish water. Subsequent to any environmental stress, these organisms proliferate in massive quantities, occasionally dense enough to give the appearance of the sea water being red. While not toxic to the mussel itself, they are deadly to mammals and birds. Long before modern laboratories and "mouse unit" testing, first nations people would dig a few clams and place them where crows could steal them. If the crows wouldn't eat them, natives wouldn't either. Although PSP most often occurs in summer, it has no season and as such can be detected year round in shellfish.

Wild mussels often contain alot of sand, or parasites and are often greatly encrusted with numerous species, including barnacles, limpets, algae or grasses, hence making them undesireable for culinary preference and marketing.

Most pearls marketed in the past century are cultured in Japanese and southern seas from Akoya and Pinctada oysters (among others). Shell bead nuclei and mantle tissues are introduced into the gonads of these invertibrates, where the defense mechanisms surround the object with a nacreous secretion, forming a pearl.

Natural pearls contain no such artifical nuclei, but are solid or near solid nacre. There is a common misconception, where pearls are formed around grains of sand, but experimentation and physical analysis of natural pearls indicate the largest volume of these pearls are formed around either foreign soft tissues of other species such as crabs and other parasites (mainly trematodes), bits of shell or injuries and fractures.

Many cultured pearls only have thin lusterous coatings, which often crack or fall away from drilling or wear. Pearl strands have knotted strings which cushion them from contacting one another. Sunlight, heat, and chemicals (such as cosmetics and deodorants) can reduce the quality of pearls over time. However, natural oils in sweat and skin can in some cases, keep pearls moist and shiny, while others can errode from continuous contact. It is recommended to clean your pearls in a lukewarm soapy (non-detergent) solution, rinsed well and lightly press dried on a soft cloth.

Natural pearls have a hardness of 3.5 to 4.5 and specific gravity: 2.65 to 2.90 

Pearls are composed partly of the mineral substance calcium carbonate and partly of a tough, horny substance of organic nature called conchiolin. Calcium carbonate may crystallize in either of two forms, calcite or aragonite. Compositions separate nacreous from non-nacreous pearls.

Each of these pearls are unique in their own way. They vary in colours from pure white to black and range in sizes from 2mm to 1.3cm. The predominant colours are champagne and rose and are not exclusive to any one specimen.

This specimen yielded four different colours within millimeters of each other.

In shelled molluscs the mantle secretes the shell. In molluscs, a muscular sac or tube-shaped organ around the outer part of body; encloses cavity containing gills and in cephalopods by contracting expels water through funnel.  In bivalves the mantle is a layer of tissue next to the shell.  In gastropods the mantle is on the dorsal side and attached to the shell.  In cephalopods the mantle enfolds much of the visceral mass behind the eyes, encloses the mantle chamber, and is contracted for jet propulsion. Natural pearls can occur in the mantle tissues of many species of molluscs, including gastropods and cephalopods (abalone and octopus). Very rarely are pearls present at the exterior edges of the mantle in mature specimens. In mussels, they tend to be predominate in or near the pallial blood sinus, as opposed to the gonads or against the shell (blister pearls) of other known species.

In bivalves, a U-shaped "dip" in the pallial line near the posteroventral margin of the shell.  Often seen in bivalves with long siphons. These represent the attachment scar of the siphonal retractor muscles, which allows the siphons to be withdrawn into the shell before closing the shell. Although greatly lower in incidence, larger pearls are found along this margin.

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My History

Although I have been quietly studing pearls for nearly 3 decades, I have recently decided to make
many of my findings public.

Background:


I first arrived in British Columbia in 1979, where I was a deepsea diver, harvesting a multitude of
marine animals and plants for commercial and scientific purposes. Initially targeting geoducks and
sea urchins, I worked several other contracts including octopus, scallops, sea cuccumbers,
barnacles and kelp. I was forced to retire from commercial diving at age 26, because of a genetic
predisposition to arthritis. I continued my interest in inverebrate biology, while commercially
harvesting clams and barnacles from the intertidal regions of the Pacific Ocean.

Many of the projects were unique in nature and pioneered much of what we know today with respect to
sustained management, recruitment and mariculture. In 1985, I applied to the BC government for two
nearshore leases. One was to experiment with clam culture (Venerupus phillipinarum) and the other,
for pearl culture experimentation.

While surveying for optimal locations for clam culture, I inadvertantly stumbled upon a remarkable
location. Near Tofino, BC, is a magnificent place, known as Meares Island. This site has
outstanding significance, in that it's deeply seated in the old growth rainforest and is largely
pristine, absent of major pollution sources and industrialization. Located in the heart of Meares
Island, is an inlet (approx 3 kilometers in reach) known as Lemmens Inlet. Within this inlet is a
small island, locally known as Lagoon Island. Aptly named, a twenty-five hectare intertidal lagoon
is encompassed by forested upland. While islands and bays are not uncommon to the region, Lagoon
Island has unique characteristics, both geographically and scientifically.

Lemmens Inlet, to this day, supports major fisheries in clams and crabs. Nutrient rich sea water
and proximity to southern exposures make this inlet one of the most prolific marine environments on
the planet. There are more species per unit square than anywhere, second only to the Red Sea. As
such, it's a mecca for off-bottom mariculture, particularily oysters. There are several leases,
which produce approximately 50,000 gallons of shucked oysters annually. Oysters from Tofino are
highly prized on the world stage, mainly because of exceptional water quality and food sources.

The Species:

The rocky shoreline is predominated mainly by fucus and blue mussels (Mytilus edulis), while the
gravel or boulder shores are largely inaccessible, owing to massive reaches of mudflats and eel
grass beds. Lagoon Island however, gives rise to the natural recruitment of the California mussel
(Mytlius californianus). California mussels normally grow in massive colonies along the surf
pounded shoreline of the greatest exposures to the Pacific Ocean, so it's occurrence as an adjunct
species in protected waterways, is certainly anomalous.

California mussels, are not considered a food source in Canada. While they are harvested as food in
other regions, particularily Mexico, there are numerous scientific and asthetic reasons for not
harvesting them in Canada. The main issue is paralytic shellfish poisoning. Mytilus californianus
is among the highest for uptake and retention of these naturally occurring organisms, which can be
deadly to humans. Next, they tend to heavily encrusted with barnacles and other organisms, which
make them visually undesireable to the marketplace and lastly, they are often very sandy.

California mussels are naturally very prolific. Unlike oysters or clams, there is little to no
incentive to condition these bivalves to spawn as brood or harvest stocks. I was wholly dependant
upon wild stock harvesting and management to maintain sustainability of the resource within the
region.

My study of mussels was not limited to Lagoon Island. For many years, I examined the physiology of
Mytilus c. from several regions stretching the entire BC coastline from Victoria to Alaska. During
these surveys, I discovered morphological variations due to genetics, as opposed to environmental
effects. While hybridization of these variants make up the biomass on the whole, there is evidence
of "veins" which are distinct from hybrids. While nearly identical in general, the variations are
predominantly noteable in the valves. Externally, some have ridges while others do not. The main
difference (for my purposes) however, are the color, thickness and crystalline structure of the
nacreous components. Most California mussel shells have silver/grey linings, while one particular
variant has a thicker and whiter presentation, presumably because the individual crystals within
the prismatic structure are dissimilar in size than the hybrids.

Harvesting these variants for culturing was an issue unto itself. While no established fishery is
ongoing within the province, the Department of Fisheries and Oceans was unwilling to develop a
harvest plan for a single user, although I was "unofficially" allowed to harvest in small amounts
for research purposes. Harvesting and transporting mussels from exposed regions was no easy task.
High seas, rogue waves and slippery conditions made the task often dangerous at best. Beside the
obvious perils of shoreline dynamics, the mortality from relaying mussels was high, even before
implantation.