Core Collections Overview

Q: Can I add an existing Asset to a Collection?

Yes. Use the update instruction with newCollection: collectionId and newUpdateAuthority: updateAuthority('Collection', [collectionId]). You can also use the CLI with mplx core asset update --collection.

Q: Can I remove an Asset from a Collection?

Yes. Use the update instruction with newUpdateAuthority: updateAuthority('Address', [yourWallet]) to detach the Asset. You can also use the CLI with mplx core asset update --remove-collection.

Summary

A Core Collection is a Solana account that groups related Core Assets under shared metadata and plugins.

Collections store a name, URI, and optional plugins that apply to all member Assets
Assets reference their Collection via the collection field at creation or update time
Collection-level plugins (e.g. Royalties) propagate to all member Assets unless overridden at the Asset level
Creating a Collection costs ~0.0015 SOL in rent

Jump to a task: Create Collection · Fetch Collection · Update Collection · Add/Move/Remove Assets

What are Collections?

A Core Collection is a group of Assets that belong together as part of the same series or set. To group Assets together, you first create a Collection account that stores the shared metadata — collection name and image URI. The Collection account acts as the front cover for your collection and can also hold collection-wide plugins.

The data stored and accessible from the Collection account is as follows:

Field	Description
key	The account key discriminator
updateAuthority	The authority of the collection
name	The collection name
uri	The URI to the collection's off-chain metadata
numMinted	The total number of Assets ever minted into the collection
currentSize	The number of Assets currently in the collection

Core Collections only group Core Assets. To work with Token Metadata NFTs use mpl-token-metadata. For compressed NFTs use Bubblegum.

Managing Collection Membership

Assets can be added to, moved between, or removed from Collections after creation using the update instruction on the Asset. These operations change the Asset's update authority — adding sets it to the Collection, removing reverts it to a wallet address.

Operation	Description	Guide
Add an Asset to a Collection	Assign a standalone Asset to this Collection	SDK · CLI
Move an Asset to another Collection	Transfer an Asset from one Collection to another	SDK · CLI
Remove an Asset from a Collection	Detach an Asset so it becomes standalone again	SDK · CLI

You must be the update authority of the Collection (and the Asset, if it's standalone) to change membership. Moving between Collections requires authority on both the source and target Collection.

An Update Delegate listed on the Collection can also perform these operations — removing any Asset from the Collection, and adding Assets it has authority over — without the root update authority's signature.

Notes

Assets can exist standalone without a Collection — a Collection is not required
Collection plugins are inherited by member Assets unless the Asset has its own overriding plugin of the same type
numMinted counts all Assets ever created in the collection; currentSize is the live count
Collections cannot be closed while they contain Assets — remove all Assets first

Quick Reference

Program ID

Network	Address
Mainnet	`CoREENxT6tW1HoK8ypY1SxRMZTcVPm7R94rH4PZNhX7d`
Devnet	`CoREENxT6tW1HoK8ypY1SxRMZTcVPm7R94rH4PZNhX7d`

Collection Operations

Operation	Page	SDK Function
Create a Collection	Create Collection	`createCollection`
Fetch a Collection	Fetch Collection	`fetchCollection`
Update Collection metadata	Update Collection	`updateCollection`
Update a Collection plugin	Update Collection	`updateCollectionPlugin`
Add/Move/Remove Assets	Updating Assets	`update` (on the Asset)

Cost Breakdown

Item	Cost
Collection account rent	~0.0015 SOL
Transaction fee	~0.000005 SOL
Total	~0.002 SOL

FAQ

What's the difference between a Collection and an Asset?

A Collection is a container that groups Assets together. It has its own metadata (name, image) but cannot be owned or transferred like an Asset. Assets are the actual NFTs that users own.

Can I add an existing Asset to a Collection?

Yes. Use the update instruction with newCollection: collectionId and newUpdateAuthority: updateAuthority('Collection', [collectionId]). See Add an Asset to a Collection for SDK code, or use the CLI: mplx core asset update <assetId> --collection <collectionId>.

Do I need a Collection for my NFTs?

No. Assets can exist standalone without a Collection. However, Collections enable collection-level royalties, easier discoverability, and batch operations.

Can I remove an Asset from a Collection?

Yes. Use the update instruction and set newUpdateAuthority to updateAuthority('Address', [yourWallet]) to detach the Asset. See Remove an Asset from a Collection for SDK code, or use the CLI: mplx core asset update <assetId> --remove-collection.

What happens if I delete a Collection?

Collections cannot be deleted while they contain Assets. Remove all Assets first, then the Collection account can be closed.

Glossary

Term	Definition
Collection	A Core account that groups related Assets under shared metadata
Update Authority	The account that can modify Collection metadata and plugins
numMinted	Counter tracking total Assets ever created in the Collection
currentSize	Number of Assets currently in the Collection
Collection Plugin	A plugin attached to the Collection that may apply to all member Assets
URI	URL pointing to off-chain JSON metadata for the Collection