I think a lot of it came from the dessert and surrounding areas. Namibia has a somewhat strange condition where the wind moves today the ocean then back inland throughout the day, so some of it I think is from the land. This was also near the famous beach area where the tide comes in very quickly and you may have seen vehicles trying to race the tide to get to higher ground. I think also near there was a salt processing facility. So, I'm not exactly sure, but it was pretty!