No. Both authenticity analysis and value estimation are professional paid services. To receive a professional opinion on your item, you must commission a Preliminary Appraisal.

A Preliminary Appraisal is an initial professional analysis, conducted remotely based on photos, information, and provenance elements provided by the client. Its purpose is to assess probable authenticity, estimate market value, and guide on next steps.

The certificate is a formal document intended to professionally document the item's authenticity, when there are sufficient elements to support it.

Yes. In some cases, the evidence allows for a conclusion that an item is authentic or inauthentic. In others, the available information does not allow for a sufficiently confident conclusion, and the result remains inconclusive.

Not necessarily. For items with many signatures, such as a soccer jersey signed by a team, the analysis may focus on a few representative signatures and the item as a whole, including the arrangement of the signatures, the medium, and the provenance.

The individual identification and analysis of all signatures are not necessarily part of the Preliminary Assessment.

Market value is estimated primarily by comparing it with historical sales of identical or similar items sold in Brazil and abroad.

The item's strengths and weaknesses are also considered. The estimate corresponds to the market value and does not include any negotiations with buyers, intermediary commissions, packaging and transport costs, or taxes, which vary according to the chosen method of sale.

Not for authenticity determination. The professional opinion is that of Mathias Meyer and is based on graphic comparison, provenance analysis, and other relevant elements.

Artificial intelligence tools may eventually be used to support contextual research or text review, but they do not replace professional analysis.

Mathias Meyer has been working in the autograph and historical documents market since 2010. He is a member of the International League of Antiquarian Booksellers (ILAB) and has analyzed thousands of autographs, manuscripts, and collectibles for collectors, lawyers, auction houses, institutions, and sellers in Brazil and abroad.

Some appraised items may subsequently be sold through direct sale or auction. However, only items approved in the Preliminary Appraisal and certified are offered to our clients or partners, ensuring greater transparency and security.

The Preliminary Assessment is carried out individually and requires a specific analysis of each item. Therefore, we do not offer quantity discounts.

For collections, large quantities of items, or specific projects, please contact us for a customized quote.

We specialize in autographs and historical documents, including letters, manuscripts, dedications, photographs, books, signed artworks, shirts, balls, and other collectible items.

For other categories, such as antique books, jewelry, watches, luxury handbags, and vintage cars, we rely on partner specialists in Brazil and abroad.

Via WhatsApp or email, send clear photos of the item — front, back, sides, and important details — and provide the name of the signature's author, if known.

It is also important to share all available information about the provenance: where, when, for whom, and in what context the item was obtained.

The Preliminary Assessment represents the professional opinion of Mathias Meyer, based on the elements available at the time of analysis.

If you disagree with the conclusion, we recommend requesting a second opinion from another expert recognized by the market. The fee for the Preliminary Assessment is non-refundable.

The appraisal is sent within 24 hours after receiving the photos and necessary information for the analysis.

Yes. Preliminary appraisal can identify the interest and potential value of an item, but Glórias can also offer, separately, an acquisition consultancy service. This service can include communication with the auction house, participation in or monitoring of bids, organization of payment and transport, as well as coordination of import to Brazil, including with a customs broker when necessary.