Is it an A8?

[Dr. Guitar]

I have some magnets i bought from RS Guitar works. They list that they have A4 magnets, however, some that I have look different. 2 of them have A2 written on them, and another A8. The A8 one looks kind of sparkley, and has some small ridges going the length of the bar. The 2 surfaces that would contact the slugs and keeper bar in a humbucker are polished smooth.

I ask here, because if they mistakenly gave me something other than A4's, I assume they won't know what i am talking about.

[J S Moore]

The A8 I have is smooth but greyish looking ( kind of un-polished) rather than shiny. I don't know if that's standard though.

[Sam Lee Guy]

Sound like a sintered magnet - looks almost like wood grain? For vintage sound Alnico should be individually cast.

[Zhangliqun]

All the A8's I've seen are dark gray on top and bottom and shiny on the sides. Don't know why.

[SkinnyWire]

Zap it with a magnet charger. A8 should measure about twice the Gauss of A4 or A2 fully charged. I have both rough and machine finished A8 - both of course machined on the poles.