Representing the price per share or per unit of warrants or rights outstanding.

No definition available.

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Namespace Prefix:	mtal_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

The period of time which must elapse after completion of a business combination before the Sponsor can transfer, assign or sell any Founder Shares unless other specified conditions are met.

+ References

No definition available.

+ Details

Name:	mtal_ThresholdPeriodForNotToTransferAssignOrSellAnySharesOrWarrantsAfterCompletionOfInitialBusinessCombination
Namespace Prefix:	mtal_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21475-112644

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

+ Details

Name:	us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3255-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
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Period Type:

- Details

Name:	us-gaap_ClassOfWarrantOrRightAxis=mtal_PrivatePlacementWarrantsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=us-gaap_PrivatePlacementMember
Namespace Prefix:
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Balance Type:
Period Type:

Private Placement (Details) - USD ($)			3 Months Ended
Private Placement (Details) - USD ($)	Sep. 03, 2021	Aug. 02, 2021	Mar. 31, 2023	May 24, 2022	Mar. 31, 2022
Class A Ordinary Shares
Initial Public Offering
Warrants issued upon conversion of notes					14,373,564
Exercise price of warrant	$ 11.50	$ 11.50		$ 11.50
Class A Ordinary Shares \| Private Placement Warrants
Initial Public Offering
Number of shares per warrant		1
Price of warrants		$ 11.50
Private Placement
Initial Public Offering
Warrants issued upon conversion of notes	201,971
Number of shares per warrant	1
Price of warrants	$ 1.50
Aggregate purchase price	$ 302,956
Exercise price of warrant	$ 11.50
Private Placement \| Private Placement Warrants
Initial Public Offering
Warrants issued upon conversion of notes		5,333,333
Price of warrants		$ 1.50
Aggregate purchase price		$ 8,000,000
Private Placement \| Class A Ordinary Shares \| Private Placement Warrants
Initial Public Offering
Threshold period for not to transfer, assign or sell any of their shares or warrants after the completion of the initial business combination			30 days