Jewelry in Cristalljoia Minerals in the center of Barcelona Raw minerals in Cristalljoia Minerals in the center of Barcelona
Master Crystals in Cristalljoia Minerals in the center of Barcelona Polished minerals in Cristalljoia Minerals in the center of Barcelona
Amethyst in Cristalljoia Minerals in the center of Barcelona Quartz in Cristalljoia Minerals in the center of Barcelona
Carvings in Cristalljoia Minerals in the center of Barcelona Tumbled stone in Cristalljoia Minerals in the center of Barcelona
Selenite in Cristalljoia Minerals in the center of Barcelona Rose Quartz in Cristalljoia Minerals in the center of Barcelona
Tourmaline in Cristalljoia Minerals in the center of Barcelona Cabochons in Cristalljoia Minerals in the center of Barcelona
Our minerals in the shop A-Z listing
Mineral hardness game at Cristalljoia

-Mineral curiosities, access to the BLOG-

Shape tells the story: how to read a mineral by its crystal habit

Learn to read a mineral by its outer shape: what crystal habit tells you about how, where and how fast each stone formed.

Read more
News

Tourmaline comes in far more than just black

Pink, green, blue, black, watermelon... each color is the result of a different chemical composition. The same mineral, endless possibilities.

Read more
News

Emerald, sapphire, ruby. Raw and cut. Same stones, two prices.

An emerald can cost €3 or €30,000. It's the same mineral: what changes is whether the crystal is transparent or not.

Read more
News

Sodalita vs lapislázuli, dos azules, 6.000 años de diferencia

Read more
News

What determines the value of a mineral?

The value of a mineral isn't in its name. It's in how it formed, and in how unlikely it is that nature created exactly that piece.

Read more
News

Uruguayan amethyst: small points and deep violet. Brazilian: large and lighter. Why?

Why does natural amethyst from Uruguay have small points and such a deep violet, while natural amethyst from Brazil has large crystals and a lighter colour? We explain it all here.

Read more
News

Cristalljoia - Barcelona

RockShop - CrystalShop in the heart of Barcelona


Minerals from all over the world for all over the world. More than 40 years in the purchase and sale of minerals, retail and wholesale.

From the center of Barcelona shipments to Spain and the rest of the world.

In the center of Barcelona, between Plaza Sant Jaime and Vía Layetana. Yellow Metro L4 (Jaume I est.).

In our physical store in the center of Barcelona we have much more variety than what is added on the web.

You can contact us without obligation at our email cmd@cristalljoia.com or whatsapp +34-670-61-16-63.

At Cristalljoia Barcelona we have a wide variety of minerals in a multitude of forms.

  • Raw minerals and rocks and 4x4 boxes for collection
  • Minerals in jewelry: bracelets, necklaces, pendants, earrings, rings...
  • Minerals for esotericism
  • Minerals for decoration

Do not hesitate to contact us if you have any questions or want us to show you the minerals that we have.

3D virtual tour of our store in the heart of Barcelona

virtual tour 3d Cristalljoia

Natural black tourmaline (unpolished)

One of the most surprising properties of black tourmaline is its pyroelectricity, which means it generates electricity when heated.

Read more
News

Make a sliding knot for a mineral pendant

In this video, we explain how to make a pendant with a sliding knot so you can wear your minerals.

Read more
News

Make a bracelet with elastic thread and mineral beads

In this video, Jessica explains to us how to make a bracelet with elastic thread and mineral beads.

Read more
News

Questions (3)

Question form

Have you some question about our shop?

Your question can be answered by other users or the store administrator

Does clear quartz have any actual structure inside it, or is it just solid glass-like stone? Sometimes I see faint lines or veils inside mine and I cant tell if thats a flaw or natural.

0 votes

Not a flaw, and not glass. Clear quartz is a true crystal with an ordered atomic structure, which is why it grows into six-sided points. Those veils and lines are natural: usually healed fractures, trapped fluid inclusions, or growth phantoms from earlier stages of growth.

Reply by Jèssica & Marc on 07/04/2026 Seller response
0 votes

Ive heard some crystals can fade or lose their colour if you leave them in the sun. Is that true, and does it happen to all of them or just some?

0 votes

It's true, but only for some. Delicate colours like amethyst, rose quartz, fluorite or kunzite can slowly fade in strong direct sun, while stones like malachite, lapis lazuli or agate never do. Just keep the fragile ones out of harsh sunlight.

Reply by Jèssica & Marc on 07/03/2026 Seller response
0 votes

Why does amethyst turn from purple to yellow (becoming citrine) if you heat it up?

0 votes

It comes down to the iron impurities trapped inside the quartz and what heat does to their oxidation state. Amethyst gets its purple color from traces of iron built into the quartz structure, held in a particular oxidation state that absorbs light in a way that reads as purple. When you heat the stone (usually somewhere around 300-400°C), that iron gets pushed into a different oxidation state.

Reply by Jèssica & Marc on 07/01/2026 Seller response
0 votes
Product added to wishlist
Product added to compare.

Looking for a mineral? Write us