blue sapphire trading has been a ra

blue sapphire trading has been a rather
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sluggish business, since entrepreneurs stopped mining due to higher manufacturing cost. As
a result, opportunity arises for black spinel and black spinel jewelry thanks to its large quantity
and relatively affordable price. Kanchanaburi’s largest trading centers of colored stones,
including black spinel, are the gemstone market near the River Kwai Bridge in the capital
district and the gemstone trading area in Bo Phloi district.
Nin or black spinel from Bo Phloi in Kanchanaburi is considered as one of the world’s
best quality black spinel. Local businesses, most of which are small-sized enterprises, have
developed their polishing process, passing on knowledge and experience in their family from
generation to generation, and then transfer this know-how through more formal educational
channels such as factories, workshops and manufacturing centers, as well as public vocational
training centers.