Ideally it should be matte to just-slightly-shiny black and very smooth. This article has some terrific information on the ideal oil to use (flaxseed) and method for seasoning, with actual scientific grounding.
Yes, cast iron exhibits magnetic properties. Iron is inherently magnetic due to the alignment of its electrons. To understand magnetism, it's important to understand the structure of a material.
If you're new to cast iron cooking and used to non-stick or stainless steel pans, you may not know how your cast iron should look and feel. A well-seasoned cast iron pan should be dark black, shiny, and smooth to the touch. Unseasoned cast iron has a rough look and feel until it is properly seasoned.
If cast iron is left in the sink to soak, put in the dishwasher, or allowed to air dry, it will rust. It can also happen when you store your cookware in moisture-prone environments, such as a cabinet near a dishwasher, an open cabinet in a humid location, or stored outside.
That's why our simple cleaning steps have you rub oil into your pan after each use to ensure the seasoning remains for quality cooking. You can also season your cast iron cookware in the oven. This method adds a more thorough layer of seasoning onto the entire pan, strengthening the bond to the iron.
First, the black specks you see coming off into your food are not harmful. They are most likely carbon deposits. This happens due to overheating of fats and oils. Using an oil with a low smoke point will carbonize at high temperatures and cause residue from the pores of your pan to rub off onto your food.
If your pan is not well-seasoned, scrambling eggs in it is going to be a bit of a mess. Not only will they stick like crazy, but after you pry the eggs from the pan, cleanup will be a nightmare. Yes, a well-seasoned skillet should be virtually nonstick, but when was the last time you seasoned your pan?
V-2 (class 40) Gray Iron, ASTM B48:
V-2 is ideally suited for straight wear applications and possesses the highest strength, hardness, resistance to wear and heat treat response for an unalloyed gray iron.
There is no consensus on this debate. It all seems to comes down to personal preference. Pan to pan, differences can be seen but those are mostly a result of seasoning. Regardless of texture, bad cooking results usually come about from an uneven seasoning cast iron.
Smooth Cooking Surface
Food does seem to release better on an old pan. A cast iron pan with a smooth finish is particularly beneficial for cooking omelets and scrambled eggs over the pebbly finish on new pans.
Quality cast iron should have an even surface without any pits, bumps, or irregularities. This uniformity ensures even cooking and heat distribution. High-end cast iron is often cast in sand molds, which contributes to the cookware's even surface and heat distribution capabilities.
What Metals Are Magnetic? Most metals with magnetic properties are ferrous: metals and alloys that contain iron. These ferrous metals include mild steel, carbon steel, stainless steel, cast iron, and wrought iron.
Common cooking oils like olive oil will gradually produce seasoning, but won't be as effective as grapeseed oil. Canola, other vegetable oils, and shortening are a little better.
Can I soak my cast iron pan? No! Soaking cast iron in water is a recipe for rust. If you need to remove sticky or stubborn stuck-on food, use a nylon scrubbing brush or a pan scraper and rinse under warm water.
Clean your cast-iron skillet each time you use it. Doing so prevents stuck-on food from staying on the skillet between uses. If the skillet is only slightly dirty, a quick wipe after cooking in it will work. If dirtier, or food is stuck, then scrubbing it is best.
Mild steel materials are ductile. The malleability of mild steel is more than that of cast iron and not as much as that of fashioned iron. Cast-iron isn't ductile. Mild steel is stronger than cast iron in both tensile and compressive strengths, yet cast iron is modestly contrasted with mild steel.