सुवर्णं पूर्वं निकष्य पश्चाद्वर्णिकां निकषयेत् ॥ कZ_०२.१३.१७ ॥
suvarṇaṃ pūrvaṃ nikaṣya paścād varṇikāṃ nikaṣayet
Primero frota el oro en la piedra de toque; después frota en ella el patrón de color de referencia (varṇikā) (para comparar).
It fixes the unknown sample’s streak first, then immediately compares it to a known standard under the same surface conditions—reducing dispute and manipulation.