Oilstones, like the Norton whetstone, can be made out of natural or synthetic material like Novaculite, Aluminium Oxide, or Silicon Carbide. As per the name, oilstones require the use of oil as you sharpen your knife's blade. This type of stone is slower at sharpening or honing a blade and it can be messy and you need to always have some oil on hand but it creates a nice sharp edge and a beautiful polish.
Mine came plain white then started to darken after a few weeks. About 4 weeks in it settled to a more natural stone/slate grey. The leather has darkened a bit too and remains soft and comfortable. The leather remains easy to adjust and my selected sizings stays in place firmly. Overall It feels, looks and works great. The knot and darker stone/leather compliment each other well.
Sharpal 102N 5-in-1 Knife and Hook Sharpener features Sharpal 102N 5-in-1 Knife and Hook Sharpener features pre-set crossed carbides for quick edge setting and ceramic stones for fine honing. Multi-groove sharpening stone is designed to sharpen fishhooks of various sizes. It comes with rubber over-molded body and feet for secure and comfortable grip. Moreover integrated compass built-in rust-proof ...  More + Product Details Close
Method 1: Use an Electric Sharpener. Quality electric sharpeners are an option, but I strongly discourage their use. First off, they remove a tremendous amount of material from your edge. Sharpen your knife a dozen times, and you've lost a good half-centimeter of width, throwing it off balance, and rendering any blade with a bolster (i.e. most high-end forged blades) useless. Secondly, even the best models provide only an adequate edge. If you don't mind replacing your knives every few years and are happy with the edge they give you, they'll do the trick. But a much better choice is to...

But it's a different type of sharp, according to Joe Authbert, product development manager at ProCook. "What it does is add tiny little micro-serrations onto the edge of the blade." But fear not - your smart knife won't end up looking like a bread knife, as you'll be hard-pressed to spot the serrations. "If you looked at it under a microscope, on the cutting edge, there are these little lines that generate the sharpness, rather than a waterstone which is a smooth sharp edge," says Authbert. 
I did a lot of research and bought this along with a diamond flat stone... and the henckles steel. The sharpest I got my knife (using a microscope to see the edge at 1000x) was using the diamonds stone up to 1000 grit, then straighten it with the steel, then use this stone to basically polish the knife. You are basically making the very very edge smooth and what this does is makes your blade last much longer before it needs sharpening. The edge of a knife looks like a hacksaw under a microscope so just picture making the teeth smaller. I will tell you if you use your knife on anything hard you just need a steel to realign the edge. You can do that about 5-10x before you need to sharpen it again. I learned a lot using a microscope to see the edge.