As regards the Moors of Spain, you give me the name of any Spanish or Moorish writer in Spain at the time of the Moors who wrote that the Moors in Spain were black. Quoting English, American etc who hadn't even been to Spain is irrelevant and misleading.
Now go back to school.
You still did not answer me. Why are most of the moorish coat of arms have blacks on them?
Why did most early writers of moors (shakespeare, nagaymath turquio, etc) only wrote of black moors?