Australia's Science Forum

Good Morning All

We are buying new Moh's Hardness Kits. These kits no longer have a square plate in them. What is used as a substitute?

What other items of known hardness do you use for scratching? A fingernail has hardness of 2.5 and a steel blade of a knife has hardness of 5.5.

Thanks in advance,
Rita

Is that like the back of a tile? That's what we use.

For hardness testing we use: fingernail, nail, steel blade, glass microscope slide, sandpaper/nail file, copper coin

Thanks for those items for scratching. I will organise some for next year.

What we used was like a smooth small tile. I finally found some at Serrata. 'White streak plates' is what they are called and they come in pack of 10. Different coloured streaks show when different items scratch the plate.