How do I repair the bottom of a glass vase?

Hello. What color is your vase?

I have used epoxy putty to repair a multitude of different things including ceramic wood plastic cement and Clay. It may be an option if you repair is either disguised on the bottom or if you can paint it. It’s my favorite rehab and repair medium.

Here’s some information on the epoxy putty.

It's a two-part epoxy sticky-found at big box hardware stores for about $6.

You mix press -then you can use scrape off excess (I use depleted gift card) and/or sand and paint. Cured putty is strong enough to drill through. Its a light grey putty.

Oatey Putty safely seals/waterproofs for plumbing boat repairs.... Ive used it for exterior entry door frame wood rot repair, elliptical pedal repair, multiple arts and crafts repair of furniture, pottery- wood -ceramic- concrete statues - even a garage laundry sink with a hole ( thanks for hiding that defect with carrots -previous homeowner)

Every home owner crafter or second hand shopper need a 2 part putty epoxy stick!

You can find other expensive and smaller 2 part epoxy sticks versions in the boat marine and wood repair sections this Oatey one is a great value.

Consider the epoxy putty for your repair needs.

https://www.oatey.com/2373255/Product/Oatey-Fix-It-Stick-Epoxy-Putty

If it's that valuable you can take it to a glass shop and have it sanded down or recut if there's enough left.