The house of Johya

Our method

Buy in person, check twice, always certify. Here is how each stone reaches you.

I am Vincent Renault, qualified gemologist. With my partner Dimitri Velasco, we founded Johya around one conviction: the only way to guarantee an emerald is to have chosen it yourself. Every stone in our catalogue was bought with our own hands, in person, in direct contact in the Boyacá region. This page describes what happens between that moment and the one when the stone reaches you.

Vincent Renault, qualified gemologist, co-founder of Johya

Field photograph, next expedition to Boyacá

Selection in hand, at the source

Field photograph, next expedition to Boyacá

We buy directly in Colombia, in Bogotá and in the Muzo region. No lot negotiated at a distance, no photographs sent by a broker: every emerald is examined in hand, in daylight and in shade, before any decision. We choose a stone for its color, its inner life and its potential, and we turn down the vast majority of what we are shown.

Independent gemological expertise

Field photograph, next expedition to Boyacá

On site and then on return, every stone goes through a battery of checks before any decision to buy or to list. The degree of oiling is established according to the laboratory scale, from none to moderate, and displayed as such on the listing. Nothing is hidden.

  • 10x loupe

    Reading the inclusions and looking for the flash effect, the first clue to a resin filling.

  • 365 nm UV lamp

    A wavelength more revealing than common lamps for spotting treatment residues.

  • Systematic weighing

    The weight is recorded at each stage between purchase and cutting: it is the thread running through our traceability.

  • Controlled light

    High-altitude sun saturates colors: a stone is also judged in the shade.

Certification by a recognized laboratory

Field photograph, next expedition to Boyacá

Every stone intended for sale goes to an independent laboratory, in Bogotá or in Europe: GIA, CDTEC or Gübelin depending on the stone. The report attests the natural origin, the Colombian origin and the level of treatment. It accompanies the stone on delivery and its number appears on the product listing.

One stone, one file

Every Johya emerald carries a unique reference. Its weight is recorded at each stage, from rough to finished stone: it is the thread linking the stone in your case to the one we chose in Colombia. Seller identified, checks dated, certificate numbered: the complete file for your stone is available on request.

Our commitments

  • Never any resin

    No resin-filled stone in the catalogue. Traditional oiling is accepted and its degree is always disclosed, even when the regulations require nothing.

  • Real photographs

    The photographs and videos on our listings show the exact stone you receive. No generated image, no color retouching.

  • Origin proven, not narrated

    We claim a mine origin only if a laboratory can attest it. Otherwise, the listing states the origin as Colombia, the only verifiable mention.

  • The price of the stone, not of the chain

    Buying direct removes the intermediaries. What you pay covers the stone, its verification and its certification.

Field photograph, next expedition to Boyacá

See the result of this method

Discover our emeralds

Read the travel notebook