Release date  22 September 2014 (Update) 

Members  Yes 
Quest  Plague's End 
Location  Prifddinas 
Examine  A crystal key can open it. 
The crystal key chest is a treasure chest located in Ivy Sophista's house in Taverley. A second chest is located in Prifddinas in the Iorwerth Clan district. The chests are locked and can only be opened by a crystal key. Attempting to open the chest without the crystal key yields the message: "This chest is securely locked shut." The crystal key is made up of a loop half of a key and a tooth half of a key; you can make the crystal key by using them with each other, or selecting the "Assemble" option.
Opening a crystal chest grants a variety of rewards, which always include an uncut dragonstone. The crystal chest in Prifddinas grants slightly better rewards than the Taverley chest. The crystal key sells for more than most of the rewards, making it generally more profitable to sell the key than to use it. The key is used once and disappears upon usage.
Rewards possibilitiesEdit
The chest loot always includes an uncut dragonstone, together with a random reward generated from 13 possible reward tables. Below are the values of the chest's contents, based on current Grand Exchange prices.
After an update, wearing a ring of wealth will increase your chances of getting a better drop.
It is only possible to obtain rune platelegs if you are a male character, and a rune plateskirt if you are female character.
Taverley chestEdit
Possibility 1  Fruit tree seedEdit
The expected value of Possibility 1 is 54,085, which is a profit/loss of 13,693 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Calquat tree seed  1  Common^{[1]}  4,958  
Papaya tree seed  1  Common^{[1]}  52,172  
Palm tree seed  1  Uncommon^{[1]}  179,868 
 ^ ^{a} ^{b} ^{c} With Possibility 1, you are guaranteed to get either a calquat tree seed, a papaya tree seed or a palm tree seed. Both the calquat and papaya tree seed have a probability of 5:11 (45.45%), and the palm tree seed has a probability of 1:11 (9%).
Possibility 2  Lantadyme seedsEdit
The expected value of Possibility 2 is 14,009, which is a profit/loss of 26,383 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Lantadyme seed  2  Always  2,244 
Possibility 3  Grimy torstolsEdit
The expected value of Possibility 3 is 20,487, which is a profit/loss of 19,905 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Grimy torstol  2  Always  8,722 
Possibility 4  RunesEdit
The expected value of Possibility 4 is 132,315, which is a profit/loss of 91,923 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Law rune  50  Always  18,100  
Chaos rune  50  Always  5,550  
Cosmic rune  50  Always  15,500  
Death rune  50  Always  8,400  
Nature rune  50  Always  22,000  
Body rune  200  Always  7,400  
Mind rune  200  Always  4,000  
Earth rune  200  Always  5,000  
Air rune  200  Always  9,000  
Water rune  200  Always  6,200  
Fire rune  200  Always  19,400 
Possibility 5  Iron oreEdit
The expected value of Possibility 5 is 58,765, which is a profit/loss of 18,373 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Iron ore  200 (noted)  Always  47,000 
Possibility 6  CoalEdit
The expected value of Possibility 6 is 36,965, which is a profit/loss of 3,427 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Coal  150 (noted)  Always  25,200 
Possibility 7  Rune barsEdit
The expected value of Possibility 7 is 52,967, which is a profit/loss of 12,575 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Rune bar  3  Always  41,202 
Possibility 8  GemsEdit
The expected value of Possibility 8 is 31,421, which is a profit/loss of 8,971 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Uncut diamond  3  Always  12,501  
Uncut ruby  3  Always  7,155 
Possibility 9  Loop half of a keyEdit
The expected value of Possibility 9 is 46,462, which is a profit/loss of 6,070 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Loop half of a key  1  Always  19,697  
Coins  15,000  Always  15,000 
Possibility 10  Tooth half of a keyEdit
The expected value of Possibility 10 is 49,957, which is a profit/loss of 9,565 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Tooth half of a key  1  Always  23,192  
Coins  15,000  Always  15,000 
Possibility 11  Rune platebodyEdit
The expected value of Possibility 11 is 49,071, which is a profit/loss of 8,679 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Rune platebody  1  Always  37,306 
Possibility 12  Rune platelegs or plateskirtEdit
The expected value of Possibility 12 is 48,439 for male characters and 48,471 for female characters, which is a profit/loss of 8,047 for male characters and 8,079 for female characters, if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Rune platelegs  1  Common^{[1]}  36,674  
Rune plateskirt  1  Common^{[1]}  36,706 
 ^ ^{a} ^{b} With Possibility 12, you are guaranteed to get either a rune platelegs or rune plateskirt. Male characters will always receive a rune platelegs, while female characters will always receive a rune plateskirt.
Possibility 13  Dragonstone armourEdit
The expected value of Possibility 13 is 5,347,557, which is a profit/loss of 5,307,165 if buying the crystal key on the GE.
 Receiving this possibility is very rare, at a rate of 1/6801.^{[1]}
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Dragonstone helm  1  Very rare^{[2]}  4,266,970  
Dragonstone hauberk  1  Very rare^{[2]}  9,758,746  
Dragonstone greaves  1  Very rare^{[2]}  4,706,609  
Dragonstone gauntlets  1  Very rare^{[2]}  3,891,029  
Dragonstone boots  1  Very rare^{[2]}  4,055,606 
 ^ https://twitter.com/JagexTimbo/status/557600452150579200
 ^ ^{a} ^{b} ^{c} ^{d} ^{e} With Possibility 13, you are guaranteed to get exactly one piece of dragonstone armour. Each piece has the same probability of being received.
Prifddinas chestEdit
This chest was released with the first part of Prifddinas on 22 September 2014, and is located in the Iorwerth Manor against the south wall. It has an improved drop table over the chest in Taverley. While the Voice of Seren is active for the Iorwerth clan, the chest provides an increased chance of Prifddinasrelated items looted, including: corrupted ore, Crystal tree blossoms, and Crystal motherlode shards. At the least, the player should still wear a Ring of wealth when opening either crystal chest.
Possibility 1  Tree seedsEdit
The expected value of Possibility 1 is 81,296.6, which is a profit/loss of 40,904.6 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Yew seed  1  Common  45,668  
Papaya tree seed  1  Common  52,172  
Elder seed  1  Uncommon  151,978 
Possibility 2  Herb seedsEdit
The expected value of Possibility 2 is 18,925, which is a profit/loss of 21,467 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Dwarf weed seed  1  Common  1,292  
Torstol seed  2  Common  5,868 
Possibility 3Edit
The expected value of Possibility 3 is 30,735, which is a profit/loss of 9,657 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Grimy lantadyme  5  Always  18,970  
Crystal tree blossom  1  Always  Not sold 
Possibility 4  TalismansEdit
The expected value of Possibility 4 is 28,956, which is a profit/loss of 11,436 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Fire talisman  5 (noted)  Always  6,525  
Water talisman  2 (noted)  Always  10,666 
Possibility 5  Rune HalberdEdit
The expected value of Possibility 5 is 87,745, which is a profit/loss of 47,353 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Rune halberd  1  Always  75,980 
Possibility 6  OresEdit
The expected value of Possibility 6 is 35,515, which is a profit/loss of 4,877 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Coal  80 (noted)  Always  13,440  
Adamantite ore  10 (noted)  Always  10,310  
Corrupted ore  50  Always  Not sold 
Possibility 7  Rune barsEdit
The expected value of Possibility 7 is 52,967, which is a profit/loss of 12,575 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Rune bar  3  Always  41,202 
Possibility 8  Uncut gemsEdit
The expected value of Possibility 8 is 31,421, which is a profit/loss of 8,971 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Uncut diamond  3  Always  12,501  
Uncut ruby  3  Always  7,155 
Possibility 9  Loop half of a keyEdit
The expected value of Possibility 9 is 31,462, which is a profit/loss of 8,930 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Loop half of a key  1  Always  19,697  
Crystal motherlode shard  10  Common  Not sold 
Possibility 10  Tooth half of a keyEdit
The expected value of Possibility 10 is 34,957, which is a profit/loss of 5,435 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Tooth half of a key  1  Always  23,192  
Crystal motherlode shard  10  Common  Not sold 
Possibility 11  Rune armourEdit
The expected value of Possibility 11 is 62,145, which is a profit/loss of 21,753 if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Rune full helm  1  Always  19,454  
Rune kiteshield  1  Always  30,926 
Possibility 12  Rune platelegs or plateskirtEdit
The expected value of Possibility 12 is 48,439 for male characters and 48,471 for female characters, which is a profit/loss of 8,047 for male characters and 8,079 for female characters, if buying the crystal key on the GE.
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Rune platelegs  1  Common^{[1]}  36,674  
Rune plateskirt  1  Common^{[1]}  36,706 
 ^ ^{a} ^{b} With Possibility 12, you are guaranteed to get either a rune platelegs or rune plateskirt. Male characters will always receive a rune platelegs, while female characters will always receive a rune plateskirt.
Possibility 13  Dragonstone armourEdit
The expected value of Possibility 13 is 5,347,557, which is a profit/loss of 5,307,165 if buying the crystal key on the GE.
 Receiving this possibility is very rare, at a rate of 1/6801.^{[1]}
Item  Quantity  Rarity  GE price  

Uncut dragonstone  1  Always  11,765  
Dragonstone helm  1  Very rare^{[2]}  4,266,970  
Dragonstone hauberk  1  Very rare^{[2]}  9,758,746  
Dragonstone greaves  1  Very rare^{[2]}  4,706,609  
Dragonstone gauntlets  1  Very rare^{[2]}  3,891,029  
Dragonstone boots  1  Very rare^{[2]}  4,055,606 
 ^ https://twitter.com/JagexTimbo/status/557600452150579200
 ^ ^{a} ^{b} ^{c} ^{d} ^{e} With Possibility 13, you are guaranteed to get exactly one piece of dragonstone armour. Each piece has the same probability of being received.
ProbabilitiesEdit
Taverley chestEdit
 The probabilities in this section are an estimation based on the data of 1134 crystal chest loots on the Taverley chest, while wearing a ring of wealth.
Possibility  Percentage 

Possibility 1: Fruit tree seed  8.02%^{[1]} 
Possibility 2: Lantadyme seeds  9.61% 
Possibility 3: Grimy torstols  9.96% 
Possibility 4: Runes  7.5% 
Possibility 5: Iron ore  8.47% 
Possibility 6: Coal  9.17% 
Possibility 7: Rune bars  9.61% 
Possibility 8: Gems  9.61% 
Possibility 9: Loop half of a key  7.94% 
Possibility 10: Tooth half of a key  6.61% 
Possibility 11: Rune platebody  5.03% 
Possibility 12: Rune platelegs or plateskirt  8.47% 
Possibility 13: Dragonstone armour  < 0.01% 
 ^ The official RuneScape wiki lists the probability of receiving a calquat or papaya tree seed at 5:11 (45.45%) each and the probability of receiving a palm tree seed at 1:11 (9%). This data shows a probability of 49.45% for the calquat, 47.25% for the papaya, and 3.30% for the palm tree seed.
Using these probabilities, the expected average profit/loss, per crystal key, when looting the crystal chest is 7,298. Assuming you will receive whichever of the rune platelegs and rune plateskirt is worth more, and the crystal key is bought at GE price. This is excluding the possibility of receiving a dragonstone armour piece, as this possibility is much too rare to estimate with any acceptable accuracy.
TriviaEdit
 The crystal key chest was reworked on 11 June 2013 with the release of the Triskelion Treasures. Previous old drops, such as receiving 2,000 coins and a Spinach roll along with an Uncut dragonstone, were removed, and new ones were added, such as the Dragonstone armour.
Chests  

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