Tall Cobalt Blue Optic Glass Vase * 15"

I call this vase "Svelte." "She's got the look." Found on a shelf... seriously hiding with other similar Indiana Glass vases. It is not Indiana Glass. I think it has the look of Italian "Optic Glass" from the 70's. Many companies were taking a shot at that technique, so I don't know who made this. Compared to similar I.G. larger vases, which are footed, this one is not footed, nor is it Cased or Lined. More slender, and the quality of the glass is better than any I.G. vase. I.M.O., either vintage Italian Optic Glass or maybe Blenko, (idk. I don't' know Blenko well enough)(the glass is thin like Italian, and I don't know if Blenko did thin Optic Glass). Or maybe, an excellent other company, or studio vase. The bottom had a pontil, which was torched leaving a distinctive dimple pattern with the glazed pontil scar still visible. The original label residue remains in the dimples, like concrete. It's an extraordinary Cobalt Blue Optic Vase and I'd like to know more about it.
15 3/8" Tall,
4 3/4" Top,
4" Base.
Thanks for looking