concrete
I am trying to build a foundry. The Youtube video refers to 4:1 Perlite:Fire Cement. But the shop also offers Fire Concrete. I don't know what's the difference.
Could someone please explain the difference?
Link to the video: https://www.youtube.com/watch?v=tTPdybtO-a0
Go back in time and wait 24 hours before using the hose. Then use it a couple of times a day for a month.
Other than that, or replacing the whole driveway, probably not. You could do various things to the surface spots, but they are exceedingly unlikely to match the rest of the surface.
You're a metal worker? How about stainless?
This DiY Headstone suggests high strength mortar mix.
You should use colorant to achieve your final color instead of attempting to stain it afterwards, which would only be skin deep.
However, this is why you use granite:
I'd suggest Uba Tuba for its flakes:
Truly though, what I'd recommend, is having a real stone cut for you. They're not as expensive as I would've thought. Even a somewhat fancy one should be under a grand. But it doesn't really matter what we think... what does The Boss want?
This:
Or this:
Food for thought, regarding the fact that you're a metalsmith, if your only tool is a hammer...
If it needs to last, then it needs to be made out of granite.
Best Answer
TLDR; - Concrete is poured into a form, for structural members. Cement is spread as a glue.
Cement is a glue. Concrete is a mix of aggregates, held together with cement.
If you're building something structural (to support a load -- such as itself), you'd buy the concrete. If you're using it as a skim/finish coat, or to attach firebrick, buy the cement, and (possibly) mix it with some very fine aggregates - depending on the use.
See this answer for more detail on cement/concrete in general. What actually happens if I vary proportions of cement and sand in mortar?
EDIT: After seeing the video, I now understand. What you are making is a light, weak concrete using the cement and perlite as an aggregate. You need to buy the fire cement, not the concrete. (You could use concrete and omit the perlite, but I think it would be pretty heavy.)