Resin casting

[wowfudge]

I've repaired a glass item which got broken. You can see the joins but it's a functional item and they won't be very noticeable. However there's one piece of glass missing about an inch square. I'd like to make a replacement piece using clear resin. Any tips as to what to use to make a mould?

Could you fill the gap with resin and cover with sellotape to get the surface smooth. I mended the handle of my favourite kitchen knife like this after it cracked up in the dishwasher.

Have you heard of kintsugi OP? It’s very interesting.

Thanks - good idea to use sellotape. My kintsugi is with super glue.

Indeed I mended my knife with Araldite.