Suggest he look at the egg you have

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This page contains details about Fallen London Actions.

He has advertised that he works on eggs.

Success

Refusal

"How am I supposed to work with this?" He vigorously shakes his head. "No, no, no. This won't support my craftmanship at all!"

Evidently he prefers to work with entirely different sorts of eggs. […]

Description summary:
The jeweller will give you a hint based on the type of egg you currently have.

Egg Type	Hint
Undeveloped	"You'll want to toughen that one up at home before you try to augment it."
Aged, Invigorated	"You might take that to the Department of Menace Eradication. Or maybe elsewhere, but that's the place I'm certain of."
Aged, Enlightened	"I hear there are some who work on that kind of Egg in the Flit. Or maybe elsewhere, but that's the place I'm certain of."
Scarlet, Invigorated	"You might find what you need in Veilgarden. Or maybe elsewhere, but that's the place I'm certain of."
Scarlet, Enlightened	"I hear there are some who work on that kind of egg at Mrs Plenty's Carnival. Perhaps elsewhere, too – but that's the one I'm sure about."
Percipient, Invigorated	"You might find what you need in Veilgarden. Or maybe elsewhere, but that's the place I'm certain of."
Percipient, Enlightened	"I hear there are some who work on that kind of egg at Mrs Plenty's Carnival. Perhaps elsewhere, too – but that's the one I'm sure about."
Pelagic, Invigorated	"You might take that to the Department of Menace Eradication. Or maybe elsewhere, but that's the place I'm certain of."
Pelagic, Enlightened	"You might find what you need in Veilgarden. Or maybe elsewhere, but that's the place I'm certain of."

[Find the rest of the story at https://www.fallenlondon.com]