A hopefully kind critique:
Seems like the containment procedures repeat and bleed over into the description, and the description feels to be a bit lacking because of this. There's a very loose connection made to the Ark of the Covenant, but in a way that leaves confusion in my mind about the writing, not a sense of mystery about the SCP.
Also, "metaphysically-shielded aluminum sarcophagus" feels a bit too much like psudo-techno babble.
Overall, it seems well written, and It certainly leaves me asking questions, though maybe not the right ones.
Possible solution:
Be more specific on the description side (including some real description beyond reference to censored SCPs), removing to some degree the containment procedures that have been mixed in, putting them in their correct section. Leaving only those details pertinent to the description.
As is, it leaves me feeling there is no SCP here, just a big hole where one should be. Everything surrounding that hole is well written, but not enough detail on the SCP to tantalize the imagination. The nature of SCP writing is such that holes exist, but generally do not omit the full description of the real object or phenomenon (exceptions exist in some cases, but then is made clear through other clues). In this case, the tenuous connection to the Ark doesn't feel to be enough.