Hello Robert,

I don't have a list of references but it's common that such slurries age with time due to normal physical processes including:

• Absorption of the continuous phase into the mineral or metal ion particles (would probably take up to 7 days or so depending on the viscosity, porosity and particle size)
• Loss of volatiles over time (depending on the continuous phase and storage conditions)
• Sedimentation - this may be unlikely if the slurry is higher in viscosity / yield stress, but possible if thinner. Would be evident from a sedimentary layer forming at the base of the container
• Loose agglomeration of the finely dispersed particles into larger clusters (with less free surface area). This could also be syneresis if a binder is present. It looks similar to sedimentation, but there is no sedimentary layer at the bottom, and there's a clear supernatent layer on the surface of the sample.

Obviously there may be other chemical reactions occurring such as oxidation, and these could be confirmed by making DSC measurements on the sample.

I hope this helps!

Best regards,

Phil