▁exceed ed ▁their ▁face ▁value . ▁ ▁After ▁a ▁three - month ▁public ▁submission ▁period ▁that ▁ended ▁on ▁ 4 ▁February ▁ 2 0 0 5 , ▁the ▁Reserve ▁Bank ▁announced ▁on ▁ 3 1 ▁March ▁it ▁would ▁go ▁ahead ▁with ▁the ▁proposed ▁changes . ▁The ▁change over ▁period ▁started ▁on ▁ 3 1 ▁July ▁ 2 0 0 6 , ▁with ▁the ▁old ▁co ins ▁us able ▁up ▁until ▁ 3 1 ▁October ▁ 2 0 0 6 . ▁The ▁older ▁ 5 0 , ▁ 2 0 , ▁ 1 0 ▁and ▁ 5 c ▁pieces ▁are ▁no ▁longer ▁legal ▁tender , ▁but ▁are ▁still ▁re de em able ▁at ▁the ▁Reserve ▁Bank . ▁ ▁In ▁August ▁ 2 0 0 5 , ▁the ▁Royal ▁Canadian ▁M int , ▁which ▁has ▁mint ed ▁Canadian ▁co ins ▁in ▁pl ated ▁steel ▁in ▁the ▁past , ▁was ▁selected ▁by ▁the ▁Reserve ▁Bank ▁to ▁make ▁the ▁new ▁co ins . ▁The ▁new ▁co ins ▁have ▁a ▁unique ▁elect romagnet ic ▁signature ▁which ▁enables ▁modern ▁v ending ▁machines ▁to ▁determine ▁coin ▁counter fe iting ▁and ▁foreign ▁co ins ▁, ▁and ▁it ▁was ▁estimated ▁the ▁change over ▁would ▁remove ▁nearly ▁$ 5 ▁million ▁of ▁foreign ▁coin age ▁from ▁circul ation . ▁ ▁The ▁change ▁to ▁smaller ▁co ins ▁is ▁also ▁advantage ous ▁to ▁Australia , ▁as ▁the ▁out going ▁ 5 , ▁ 1 0 , ▁and ▁ 2 0 c ▁co ins ▁were ▁of ▁the ▁same ▁size ▁and ▁weight ▁as ▁Australian ▁co ins ▁of ▁these