Are these earrings solid gold?

No. The gold portion is 18K yellow gold, but the earrings combine it with sterling silver rather than being solid gold throughout.

What is an omega back?

It is a hinged clasp that snaps behind the earlobe against the post, spreading the hold across more of the ear than a push back. It is more secure but bulkier.

Is citrine durable enough for everyday wear?

Citrine is a quartz, around 7 on the Mohs scale, so it resists scratches reasonably well but can chip on hard impacts. It is better suited to occasional than rough daily wear.

Can I wear these with only gold or only silver jewelry?

Yes. The two-tone design is meant to bridge both, so they pair with either metal, though the mix is most visible up close.

How should I clean them?

Wipe the metal with a soft dry cloth and clean the citrine with mild soapy water and a soft brush. Avoid ultrasonic cleaners and harsh chemicals on the stone and gold.