According to Snædal (2015; see references), from Ancient Greek ϡ (š, “sampi”), which shares the same numerical value and had a very similar shape in antiquity (see its Wikipedia article for more information on its past forms).
𐍊 • (900)
- The twenty-seventh letter of the Gothic alphabet, with a numerical value of 900 and no phonetic value.
- (Gothic script letters) 𐌰 (a), 𐌱 (b), 𐌲 (g), 𐌳 (d), 𐌴 (ē), 𐌵 (q), 𐌶 (z), 𐌷 (h), 𐌸 (þ), 𐌹 (i), 𐌺 (k), 𐌻 (l), 𐌼 (m), 𐌽 (n), 𐌾 (j), 𐌿 (u), 𐍀 (p), 𐍁 (90), 𐍂 (r), 𐍃 (s), 𐍄 (t), 𐍅 (w), 𐍆 (f), 𐍇 (x), 𐍈 (ƕ), 𐍉 (ō), 𐍊 (900)
- Snædal, Magnus, 'Gothic Contact with Latin: Gotica Parisina and Wulfila's Alphabet', in: Askedal, J.O. and H.F. Nielsen ed., Early Germanic Languages in Contact (Amsterdam 2015) pp. 91-108, especially 98.