Polycrystalline tables, polycrystalline elements, and related methods

A method of forming a polycrystalline element, comprising:

• disposing a first plurality of particles comprising a superabrasive material, a second plurality of particles comprising a superabrasive material, a catalyst material, and a third plurality of particles comprising a mass of hard material in a mold;
• sintering the first and second pluralities of particles in the presence of the catalyst material and the third plurality of particles to form a polycrystalline table having a first region comprising a first permeability and at least a second region comprising a second, lesser permeability attached to a substrate, the at least a second region being interposed between the first region and the substrate;
• and
• removing catalyst material from at least the first region of the polycrystalline table.

A method of forming a polycrystalline element, comprising:

• forming a first polycrystalline table having a first permeability;
• bonding the first polycrystalline table to another polycrystalline table having another, lesser permeability attached to a substrate;
• and
• leaching catalyst material from at least the first polycrystalline table.

A method of forming a polycrystalline element, comprising:

• forming a first polycrystalline table of superabrasive material in the presence of a catalyst material, the first polycrystalline table having a first region having a first permeability and a second region having a second, lower permeability;
• at least substantially fully leaching the catalyst material from at least the first region of the first polycrystalline table;
• and
• bonding the first polycrystalline table to another polycrystalline table of superabrasive material attached to an end of a substrate of hard material, the second region being interposed between the first region and the other polycrystalline table.