What to use to fill gaps between bricks in fireplace (and other uses)?

[Oxbow16]

Hi all

 

I have an old stone and brick fireplace and will soon be having a wood stove installed.  There are a handful of gaps between bricks, some of which are quite deep.  Would this be suitable to use to fill the gaps:

 

https://www.screwfix.com/p/cementone-general-purpose-mortar-grey-5kg/36857

 

Or should I use something more specifically heat resistant?  There is of course a lot of existing mortar which I'm guessing is probably normal stuff but who knows?! 

 

Many thanks

[Oxbow16]

ANY MODS READING THIS... 

 

I've asked about this in another thread over in the Stoves, Fires & Fireplaces Sub Forum (I wanted to ask some other questions at the same time):

 

https://forum.buildhub.org.uk/topic/18975-fireplace-recess-prep-for-multi-fuel-stove-hearth-paint-mortar-for-pointing-and-black-stuff/

 

So can this be deleted if possible please?