This cave is rich in guano.

This stone is a mineral called epidote.

Her necklace had a beautiful cat's eye stone.

Her necklace had a beautiful cat's eye stone.

We visited the ancient dolmen.

Anatase is a type of titanium oxide, characterized by the shape of its crystals.

This stone is a mineral called clinozoisite.

This beautiful stone is a mineral called clinozoisite.

This mineral is called ulexite and has special optical properties.

He succeeded in a difficult project with the spirit of 'ishi no ue ni mo sannen', which means great works are performed by perseverance.