A wooden mallet used for pounding rice

the mortar and pestle

vajra scepter (ritual object of Buddhism)

enough blood flowing to float pestles (idiom); rivers of blood

see 磨杵成針|磨杵成针[mo2 chu3 cheng2 zhen1]

to grind an iron bar down to a fine needle (idiom); fig. to persevere in a difficult task

perseverance will prevail.