Could this be 1882 equivalent in arabic, muslim calendar?
Here’s an image of the 1882 star. The “1799” is indeed an arabic numeral, but it’s 1299. The backward 7 is a 2 It’s the year according to the Muslim calendar, so dating from Muhammed’s journey to Medina in 622AD by our calendar. The writing on the obverse says “Khedive of Egypt” apparently. The 2306 on the back could well be a regimental number. Since you’re talking about the 1882 medal I can look it up on the rolls. I’ll get back to you.