Those white sections look like calcite to me which will set off the copper causing the other shades of blue/green. Usually when a customer has one leak others follow.

this blue minerals should be very easy to dissolve in hot water.
Try to put sample into glass/ jar of boiling hot water and see how easy it goes.

You could use this solution later even to make some interesting electroplate experiment.
If you hang one nail and another piece of copper in this electrolyte and connect battery to each then your
nail will be covered with copper almost in instant. If you have some sailing stuff made of iron you could protect with this thin layer of copper or just to make nicer.

A bit of background to clarify the above bit -

Back when I was in the kaboomy stuff manufacturing game my employer had a pretty impressive "oh dear" moment.

While doing an explosives magazine stocktake during the wee small hours, a brass padlock got dropped - and there was a flash of light with a distinct "POP" being heard. The sort of thing that people in our line of work tend to find a bit concerning.

No PETN residue or similar evident on the ground, which would be the easiest explanation.
However - the padlock had scorch marks on it.
The padlock and scrapings from the ground were sent to the lab. techs.

Verdict - over a long period of time, ammonia fume exposure was causing a reaction with the particular alloy used to make that batch of padlocks.
The resulting residue had a blue-ish tinge and was known to be friction and impact sensitive.

These padlocks were used to secure the hoppers of our explosives manufacturing trucks [aka "bomb trucks"]

Orders came from high up the food chain that we were to get rid of any brass padlocks and replace them with stainless steel - and at the first sign of corrosion even these were to be replaced