I am not familiar with Mint itself, but since it is a fork of Ubuntu/Debian, chances are the following will work (run as root or with sudo):
Code:
update-alternatives --config x-cursor-theme
It will give you alternative options for your cursor theme, something like
Code:
Selection Path Priority Status
------------------------------------------------------------
0 /etc/X11/cursors/core.theme 30 auto mode
* 1 /etc/X11/cursors/core.theme 30 manual mode
2 /etc/X11/cursors/handhelds.theme 20 manual mode
3 /etc/X11/cursors/redglass.theme 20 manual mode
4 /etc/X11/cursors/whiteglass.theme 20 manual mode
Press enter to keep the current choice[*], or type selection number:
The above works on Debian, I assume it should work on Mint as well.
You can also create your own cursor themes;
this website has a step-by-step guide on how to do that.