Relic EXP BookLost Crystal
Lost Crystal is a 4★ material in Honkai: Star Rail — see how to get it, its use, and related items right below on this page.
Lost Crystal is a material ★4 in Honkai: Star Rail. This item is not currently used to level up any character or Light Cone. Obtainable from 1 different sources in-game.
Last updated: 30/07/2026
The figures on this page come directly from gamevika's internal game data store (counted/read straight from the real records), not an estimate or copy from elsewhere.
Description
Enhancement material for Relics. Provides 1000 Relic EXP.
Lore
A Fragmentum dust crystal that had densified after being reduced to its original form. "This must not be placed together with the ores offered to the Amber Lord. This is a creation of the Stellaron and goes against the will of Preservation."
How to obtain
- Forgotten Hall
Stats
| Rarity | ★★★★ |
| Type | Relic EXP Book |
| EXP value | 1,000 |
| Stack limit | 99,999 |
Official names in every language
| Tiếng Việt | Tinh Thể Đánh Mất |
| English | Lost Crystal |
| 日本語 | 遺失晶塊 |
| 한국어 | 유실된 수정덩이 |
| 繁體中文 | 遺失晶塊 |
| 简体中文 | 遗失晶块 |
Where to use it / Related tools
Lost Crystal is an upgrade material — check the Material Planner to see how much you need for the character you're building.
Same-type items
FAQ
What is Lost Crystal?
Enhancement material for Relics. Provides 1000 Relic EXP.
Where do you get Lost Crystal?
Sources for Lost Crystal: Forgotten Hall. See the “How to obtain” section above for details on each source.
What type of item is Lost Crystal?
Lost Crystal is a 4★ material in Honkai: Star Rail, in the “Relic EXP Book” category.
What is Lost Crystal used for?
Lost Crystal currently isn't listed as required by any character ascension, Light Cone ascension, or crafting recipe in official data.
How much EXP does Lost Crystal give?
Lost Crystal gives 1,000 EXP when used to level up.