Help identity plaster for repair

[fields_g]

A while ago, I had some plaster let loose below the water level (3 ft below water, 4x8" oval). I believe an underwater repair is possible with something like a fast set versions of: Pool Interior - E-Z Patch , correct?

Next would be to match the existing plaster. In the previous owner's pool records, I found a renovation quote from 2002. I know a renovation was done since it was built in 1984, but don't know if this quote was from the selected renovation. Either way, the quote didn't specify the plaster to be used. Attached are two pictures of some of the plaster that has fallen out (1.5x2"). Could you help identify the plaster?

I'd guess it is the "1FS - White" or the "10FS (quartz) - NPT® ColorScapes® - White" or "10FS (quartz) SGM® Diamond Brite® Series - Oyster Quartz".

 

[PoolGate]

I doubt you'd successfully match a 15 plus year old plaster chip. It looks like that section came off totally to the gunite as well. Most likely the plaster is delaminating. Have you had a pool professional look at it?

 

[fields_g]

Thanks! You led me down a rabbit hole. Swimming Pool Pop Offs, Broken Plaster, Calcium Nodules

I have nodules, and like I said, it was re-plastered. The back of the plaster is smooth. The plaster chip also looks thinner that I would have expected. Probably need to get this looked at.

I hope that it can be stabilized even if it isn't a perfect match. Not ready for a re-plaster job.

 

[RMcGirr83]

Plaster is usually only ~3/8" thick.

 

[fields_g]

The piece pictured is no more than 1/8" on the thicker side. That seems to be very far off from 3/8".

 

[PoolGate]

Can you see gunite where it came off?

 

[fields_g]

I'm unsure. Didn't get a real good look because of depth. The back of the piece that came off is smoother than the from side.