How to calculate a derivative from a voxel.

Objective:

I would like to calculate the derivative from a Geosoft voxel (*.geosoft_voxel). 

Resolution:

1. Voxel > Utilities > Filter a Voxel

2. Select the Input Voxel and give the Output voxel a name. 
3. For the Filter parameter select: "From File"
4. For the File parameter select the derivative you would like to filter. NOTE: there are multiple options to pick from: X,Y or Z. If you where looking for a vertical derivative you would select gradient_z_VOXI.flt3d.
5. Set the Number of pass and Dummy Handing 
6. Click OK