Numount too viscous

[MikeBradley]

I occasionally use Brunel Numount when making permanent slides but over time it becomes too viscous, so i buy fresh. Warming the bottle on a coffee cup heating pad helps but not enough. Is it possible to thin Numount and if so what with?
Thanks
Michael

[mrsonchus]

It is easy enough to thin, just use 'Histoclear' - NuMount is resin-based - don't add alcohol or water or even oil to thin it! I have used NuMount to make dozens if not a couple of hundred permanent slides and it's really pretty good and has superb clarity. It may also be possible and indeed perfectly compatible (not sure though) to use Xylene - which I never use as Histoclear is a safe and direct replacement.

[MikeBradley]

Thanks John, would Histo I or II make any difference as I have neither at present?
Michael

[mrsonchus]

Thanks John, would Histo I or II make any difference as I have neither at present?
Michael

Histo' 1 for certain, I've tried Histo' 2 and Histo' 3 and while they are both less 'smelly' they do have compatibility problems with mountants. It used to be the case that they were both substantially cheaper (by as I remember about 60%!). Over the past few years their prices have risen whilst that of Histoclear 1 has remained almost static - removing the price-bonus more or less.
I soon switched back to Histo' 1 having also found good suppliers for the gallon bottles which I use with the many slides that I process and mount.

My advice based upon the past 5-6 years of mounting would definitely be to go for Histoclear 1 and forget the other 2 variants. Starting-out looking quite an indulgence to pay upwards of £100 per (U.S.) gallon, as my microtechnique and efficiency improved my use of all chemicals fell dramatically, virtually removing any real thought of cost of materials...