Type of Spiritual Experience
As an extension of the idea that caves are an area where one can learn ‘truths’ - both palatable and unpalatable - about yourself, as well as more general spiritual information, the concept of this ‘hidden knowledge’ is often represented symbolically as ‘hidden treasure’ or perhaps more correctly hidden artefacts. In effect they are objects that because of their importance in unravelling something of the subconscious are valuable to you
A Dictionary of Symbols – J E Cirlot
In most symbolic traditions, jewels signify spiritual truths; the precious stones in the garments of princesses, or in necklaces or bracelets, as well as gems shut away in hidden rooms, are symbols of superior knowledge.
…...Treasures guarded by dragons allude to the difficulties of the struggle for knowledge [truth]. - not as science in the sense of an impersonal erudition, but as the sum of experiences, and inextricably bound up with living and with evolution.
Gems hidden in caves refer to the intuitive knowledge harboured in the unconscious
A description of the experience
The allegorical tale such as that of Aladdin, is one of the tales in The Book of One Thousand and One Nights (Arabian Nights). The story describes how the young Aladdin is recruited by a sorcerer, who pretends to be the brother of Aladdin's late father. He persuades Aladdin to retrieve an oil lamp from a magic cave, which will only open upon a specific command. The allegory should be clear.
The cave is full of treasure, but the sorceror insists that Aladdin can have all the treasure, but he just wants the lamp. Aladdin becomes suspicious, however, and refuses to hand out the lamp, whereupon the sorceror in revenge locks him in the cave. Aladdin has a magic ring the sorceror gave him and when he inadvertently rubs the ring, a djinn [genie] appears who helps him escape. He takes the lamp home, still wondering why the sorceror wanted it, and when his mother tries to clean it, a second, far more powerful djinni appears, who is bound to do the bidding of the person holding the lamp. With the aid of the djinni of the lamp, Aladdin becomes rich and powerful and marries Princess Badroulbadour, the Emperor's daughter.
This is not the end of the story, but it will suffice to demonstrate the symbolism of a cave containing treasure. In this case the most valuable artefact is not the treasure but the lamp – illumination – furthermore of all the artefacts it appears to be the least valuable.