That Black Sap is 

Marshall Clam Shell Porcelain 


This Marshall Clam Shell is Really Tough and Really Sharp

Ancient Vietnam Knew For Best Sword Maker

And

They Been Using This Marshall Clam to Make Sharp Tough Sword Ever Since

+

Tough Corroded Metal Aloy

+

Rare Really Tough Hard Wood Charcoal

Main Ingredient to Make 

The Knife Sharper and Extremely Sharp Like Tough Razor

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