Espom Salt Lab (magnesium sulfate heptahydrate)

[Lyristes]

Hello, it's me again! Could someone please help me with one of my analyses of my Epsom Salt lab?

Here's my data table:
Data and Calculation Table Part I

1. Mass of crucible and cover 22.39 g
2. Mass of crucible, cover, and hydrate 24.969 g
3. Mass of hydrate 2.579 g
4. Mass of crucible, cover, and anhydrous compound 23.71 g
5. Mass after second heating (optional/omitted) n/a
6. Mass of anhydrous magnesium sulfate 1.32 g
7. Mass of water of hydration 1.259 g
8. Number of moles of anhydrous magnesium sulfate 0.01097 mol
9. Number of moles of water in the hydrate 0.0699 mol
10. Percentage of water in the hydrate (experimental) 48.82 %
11. Percentage of water, accepted 51.20 %
12. Percentage error 4.65 %
13. Moles of water per mole of anhydrous MgSO₄ 6.37 mol
14. Formula of hydrate 1 MgSO₄ 6.37 H₂O
(2 sig figs) 1 MgSO₄ 6 H₂O

How would I explain the discrepancy between my experimental value and the accepted value? Would I say that I overheated or underheated the hydrate?

[ChenBeier]

Epsom salt is Magnesiumsulfat Hepta hydrat MgSO₄ x 7 H₂O
But there ist also a monosulfat existing.

Probably a mixture.