Create Linux Mint USB on Mac OS/X

create-mint-sh

#! /usr/bin/env bash

# Insert a USB key.
# if needed initialize it with MS/DOS FAT and MBR

# Download the Mint ISO image
# Convert the ISO -> IMG
hdiutil convert -format UDRW -o  linuxmint-20.1-cinnamon-64bit  linuxmint-20.1-cinnamon-64bit.iso

# Check where the USB drive has been mounted
diskutil list

# Run a diskutil list to know the device for the USB key, e.g.: /dev/disk3
# then unmount the USB key:
diskutil unmountDisk /dev/rdisk<N>    #note the "r"

# And copy the img on it:
sudo dd if=linuxmint-17.3-cinnamon-64bit.dmg of=/dev/rdisk<N> bs=1m

# Eject the USB key and voilà!