OPALS

Online lesson: Spring 2026 Program (SESSION 3) What are opals. Basic mineralogical classification. Opal gem varieties and trade terminology. History and main occurrences. The complexity of understanding opal value factors. Main treatments and imitations.

APRIL 14, 9:00 AM or 7:00 PM (Lisbon/London timezone)

Legal information:

ALL end consumers:  VAT at a 23% is added, regardless of the client’s fiscal jurisdiction.

B2B - Please contact us before you register for assistance with business accounts for tax and invoicing purposes (see above) or for large group bookings.

Businesses in the European Union (EU)*: VAT is not added for businesses with a verified VAT number (VIES). EU member states’ reverse charge rules apply).

Businesses established in Portugal: IVA at a 23% is added. NIF or NIPC is recommended for invoicing.

Video/audio recordings: Due to local privacy law, recording of the session is strictly NOT permitted.