Blacksmiths, carpenters, coopers, masons, brickmakers, etc. Skilled artisans were if anything higher status in the nineteenth century than today, with the general term "mechanic" (meaning skilled artisan) being a recognised one and at least the equivalent of middle-class status.What high-skilled jobs? I assume you mean stuff like artisanship. Even today many people don't understand how much skill it takes, because they label it as "physical labour", under impression "physical labour"="unskilled labour".
According to this source here, the records of Mount Vernon, George Washington's estate, at the time of his death reveal that more than one-quarter of the slaves there were classified as skilled workers (carpenters, bricklayers, blacksmiths, coopers, millers, distillers, spinners, weavers, and seamstresses). This proportion at Mount Vernon may well be higher than the norm, but there were certainly enough skilled slaves to form a significant social class.
Slaves were mostly forbidden from being taught to read and write because it was considered dangerous, not because there was any doubt that they could learn to read and write. Naturally, there would be no point having laws forbidding teaching slaves to read and write if they were thought to be too dumb to learn.Slaves were not permitted to learn to write or read in many states, which demonstrates that most people were not able to cope with the concept easily, even though over time, there will less and less jobs one could do without knowing how to read and white. Even Nazis had official policy that their future slaves were to have basic knowledge of written German to be able to read instruction manuals for their work tools. But then, Nazis had different moral justification for slavery than CSA.