Page 471 - Applied Pharmacognosy

• Total ash is useful to detect drugs which have been coated

with chalk ( Ca CO3 ) , lime { Ca O & Ca (OH)2 } or Ca SO4 .

• These coatings are used as preservatives and to improve the
appearance of certain drugs as in ginger and nutmeg.

• Total ash is also useful to detect low - grade products by the
addition of earthy matter (silica ).

• Total ash is a measure of the physiological and non –
physiological ashes present in the plant material.

• Total ash is useful to detect drugs which have been
coated with chalk ( Ca CO3 ) , lime { Ca O & Ca (OH)2 } or
Ca SO4 .