Crystal chest
The Crystal chest is the unofficial name of a treasure chest in Taverley that is famous for containing dragonstones, among other things. The chest is locked and can only be opened by a Crystal key. The crystal key is made up of a loop half of a key and the tooth half of a key; you can acquire the Crystal key by using them with each other. The crystal key sells for more than most of the rewards, making it more monetarily satisfying to sell the key. When the key is used it disappears, so opening the chest is a gamble. Some times the chest will award more than one of these rewards, so you can end up with multiple amounts of the reward.
Attempting to open the chest without the crystal key yields the message: "This chest is securely locked shut."
Contents and value analysis
The chest loot always includes an uncut dragonstone and will normally include another random reward, but not always. Below are the values of the chest's contents, based on current Grand Exchange prices. Most times you have a 9 out of 16 chance to make a profit, or a 56.25% chance, however this can fluctuate due to the price of the crystal key. A Ring of Wealth now increases your chances of getting a better drop since it got updated. The frequencies below are based on a batch of 3,354 keys. It is only possible to obtain Rune Platelegs if you are a male character, and Rune Plateskirts if you are female character. These tests were done on a male character, and there were no Rune Plateskirts received. Tests on a female character have shown Rune Plateskirts as a reward.
It is a common misconception that you can obtain a Crystal Shield or a Crystal Bow from the chest. The chest does not contain either of these items, as they are a quest reward.
Image Possible loot Profit/Loss Frequency (Approx.) 
Uncut dragonstone, spinach roll, and 2000 coins −9,533
39.69%
Uncut dragonstone 
−11,533
16.72% 
Uncut dragonstone, 50 of each elemental rune, 50 body and mind runes, 10 of all other runes, excluding blood, astral, armadyl rune, and soul runes Expression error: Unexpected < operator. Expression error: Unexpected < operator.Expression error: Unexpected < operator.Expression error: Unexpected < operator. 7.73% 
Uncut dragonstone and 3 Rune bars 27,554
3.51% 
Uncut dragonstone and 100 coal (noted) 14,767
6.55% 
Uncut dragonstone and 150 iron ore (noted) 20,867
2.75% 
Uncut dragonstone, 2 cut rubies, and 2 cut diamonds 2,165
4.23% 
Uncut dragonstone, 5 raw swordfish, and 1000 coins −9,018
10.57% 
Uncut dragonstone, loop half of a key, and 750 coins −1,381
3.26% 
Uncut dragonstone, tooth half of a key, and 750 coins 1,975
3.67% 
Uncut dragonstone and adamant sq shield −9,381
1.06% 
Males: Uncut dragonstone and rune platelegs Females: Uncut dragonstone and rune plateskirt
26,530
26,495
0.26%
Based on the above table, the average profit from opening the chest is: Male player: Expression error: Unexpected < operator. Expression error: Unexpected < operator.Expression error: Unexpected < operator.Expression error: Unexpected < operator.. Female player: Expression error: Unexpected < operator. Expression error: Unexpected < operator.Expression error: Unexpected < operator.Expression error: Unexpected < operator. (prices can differ due to price differences between plateskirts and platelegs). It is not advised to try and make a profit buying keys and opening the chest because of the rare odds of some of the highest gains (such as double dragonstones). nl:Crystal chest fi:Crystal chest