Peyare bhai
Pure carnuba is in hard stone shape which can't be use as car wax so to make it useable on car skin have to add some more things
Pure carnuaba not means wax is 100% based on carnuaba but its mean what ever qty of carnuaba use in it is purify , usualy car waxes avilable in market having 20 to 35% carnuaba and some rarely upto 50%
Carnuaba is very expencive so the waxes having more % of carnuaba very expencive
Not only % but quality of carnuaba also matters , like more purify carnuaba more expencive in price
Mother step 3 good wax , better than meguiare but less life and its also a chractristic of carnuaba as its itself life short 
Yes mother step 3 good wax having more % of carnuaba but not very purify one as purify one cansell at rs 1800 to 1900 