Slate is much more commonly found in wet areas, especially around rivers in the United States, so it wouldn't be very available to Natives who were more inland.
It was a mixture of various reasons, although for the Spanish and Portuguese it was a question of reaching India for spice trades after the embargo instated on them by the Ottoman Turks.
The Portuguese went around Africa, and the Spanish tried sailing west across the barren ocean, and accidentally discovered America through Columbus.
<span>An educated financial and social elite in European colonies in the Americas.</span>
I Would say it is India and japan
