Matching mortar colour after already filled.

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I've had to replace bricks in several parts of the house over the years and never managed to get a good match on the original mortar colour.

Originally I thought it was yellow sand and the result was nothing like the original (too light grey). Red sand resulted in dark grey finish. I realise now that it was sharp sand used, because the cement colour I was trying to match is barely visible and it's the sand that you can see in the joints now.

I really am not in a position to get the whole house repointed at the moment, so could you please tell me what products are available to change the colour of the mortar and get the best blended finish?
 
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Still think so? I'm putting this through brick acid to see what the colour is after all traces of cement removed.
fkcT3tB.jpg
 
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After going through brick acid and drying for two days, this is what it looks like in direct sunlight.

McfZULL.jpg


Which colour do you think now?
 
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After going through brick acid and drying for two days, this is what it looks like in direct sunlight.

McfZULL.jpg


Which colour do you think
You have to match the colour on the wall, not after washing the cement out, to me either smoke or light khaki, order samples and try them even mixing the two, it can be diluted to lighten the colour if needed, iv'e never done this myself, only seen it being done by others, and it does work.
 
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Just remember if you do any mixing to get the proportions the same for the next mix. I've done it when mixing colours and run out before I'd finished and had a bit of trouble getting a bit more to match.
 
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Thanks for your replies. The mortar on the walls is the colour of the sample pot, as the cement film created by pointing has been washed and blown away so that the sand is exposed.

It's clear the sand used is sharp sand, because it contains lots of little stones. I need to replicate that if/when I get a chance to repoint and am wondering if sharp sands come in different colours/shades, because I really want to know how to end up with the same colour.
 
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Have you tried using yellow sand with less cement added? Maybe a 5:1 / 6:1?
You can also try snowcrete.

That mortar looks identical to my house - 1960's ish. I did match it pretty well once - I wish I had written down what I used. I seem to remember snowcrete + grey cement and yellow sand from Jewson's.

When testing use the mortar between some old bricks rather than a lump somewhere...
 
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You are right, the property was built in 1958! I've been using 4:1 and only when I used sharp sand did I get a matching texture.

I obtained the sample by rubbing using a hard brush between bricks and catching it with a dust pan, before cleaning it with brick acid and then water.

In the past I have used various mixes using red or yellow sand mixed with cement and some also with hydrated lime, I'm pretty sure I never tried a weaker mix than 3:1 though.

The result was always a grey appearance because of the cement. The hydrated lime made the colour of the mix a lighter grey, but it was still grey.

I'm a bit concerned about using a weaker mix than 4:1. As the original mortar contains various stones, am I right in thinking that it must be sharp sand?
 
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You are right, the property was built in 1958! I've been using 4:1 and only when I used sharp sand did I get a matching texture.

I obtained the sample by rubbing using a hard brush between bricks and catching it with a dust pan, before cleaning it with brick acid and then water.

In the past I have used various mixes using red or yellow sand mixed with cement and some also with hydrated lime, I'm pretty sure I never tried a weaker mix than 3:1 though.

The result was always a grey appearance because of the cement. The hydrated lime made the colour of the mix a lighter grey, but it was still grey.

I'm a bit concerned about using a weaker mix than 4:1. As the original mortar contains various stones, am I right in thinking that it must be sharp sand?

I'm not a brickie so I cant really comment on using more sand than cement. With thermalite type blocks you use a 6:1 as they are soft, however this wouldn't be externally facing. It certainly still goes off rock hard.

You have to remember the sand you have sampled is mixed with 60 years of dirt too!

Try a 5:1 and see what happens, or if you are concerned buy a bag of snowcrete (white cement). Its about £12 a bag though!!!

As for the stones... I think the grading process was just more generous back then. Perhaps sieve some sharp sand for the smaller stones to make it look right?
 
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Your sand looks like it's a soft building soft, with rounded particles. This would be normal, as laying bricks with a sharp sand and cement is quite difficult.
The particles in sharp sand are more angular in shape and lock together.
 
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Your sand looks like it's a soft building soft, with rounded particles. This would be normal, as laying bricks with a sharp sand and cement is quite difficult.
The particles in sharp sand are more angular in shape and lock together.
Regular building sand is very fine by comparison though. I haven't come across any regular sand with particles/stones this size in them (3-4mm). That's why I assumed sharp sand, because that does have larger particles/stones in it. I'd love to know which builders sand was used and/or which is the closest I can get hold of now in terms of colour and texture.
 

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