Gemstone working apparatus

Gemstone abrading apparatus which comprises:

• a rotatable base;
• at least two gemstone abrading members including:
• a first gemstone abrading member which defines a first gemstone abrading surface and which is removably mountable onto said base;
• and
• a second gemstone abrading member which defines a second gemstone abrading surface, of a different grain size than that of said first gemstone abrading surface, and which is removably mountable onto said base concentrically with said first gemstone abrading member;
• and
• rotational height adjustment means for adjustment of the height of said second gemstone abrading member by rotation thereof relative to said first gemstone abrading member to any non-predetermined-rotational position, thereby to bring said second abrading surface into planar alignment with said first abrading surface so as to provide a combination abrading surface of varying grain size and of uniform level;
• said height adjustment means, including:
• first stepped means provided in said base;
• second stepped means provided on said second abrading member for engaging said first stepped means;
• and
• means for selectably securing said second gemstone abrading member in a selected, non-predetermined rotational position relative to said base,
• wherein said first stepped means defines recessed portions and raised portions and said second stepped means defines raised portions and recessed portions corresponding to said recessed and raised portions of said first stepped means, and wherein, in a relatively lowered position, said raised and recessed portions of said second stepped means respectively engage said recessed and raised portions of said first stepped means, and wherein rotation of said second abrading member relative to said base causes said raised portions of said second stepped means to engage said raised portions of said first stepped means, thereby to raise said second gemstone abrading member relative to said base.