Generally, the instrument is a check, cash or a credit card.
If, however, you want to verify that the stone that you are buying is a diamond, you need a diamond tester.
Rheostat is the name of an instrument used to vary electrical resistance.
A jeweler's loupe, which is a special magnifying tool, is commonly used to examine diamonds closely for their clarity, color, and any imperfections. Additionally, tools like a diamond tester can be used to verify the authenticity of the diamond and to determine if it is a real diamond or a simulant.
syringe
Timepieces.
a compass i think
Bongos.
A set square !
Telescope.
Electronic microscope
Amy diamond was a name once concieved but never used by a student journalist,derived from The Diamond newspaper in Victoria
The instrument used to measure the volumes of liquids are many as follows ..they are : beaker ,burette,pipette,etc.
Practically, 'Italian diamond' is used to modify other words, such as jewelery. In this case, then, 'Italian diamond' could be a brand name.