The configuration presented is NOT intended to be used on the public network. These are the parameters used for the Catapult Testnet version (MIJIN_TEST).

Fixed Asset

Mosaics are part of what makes the Smart Asset System unique and flexible. They are fixed assets on the NEM blockchain that can represent a set of multiple identical things that do not change.

Each mosaic is defined by a variety of attributes such as name, quantity, divisibility and transferability.

A mosaic could be a token, but it could also represent a set of more specialized assets such as: reward points, shares of stock, signatures, status flags, votes or even other currencies.

Mosaic definition transaction

Mosaic definition transaction is used to create a new mosaic.


A mosaic is always linked to a namespace, like a file hosted on a domain.


Like a website and directory, a mosaic can have the same name as other files on other domains. However, a namespace + mosaic is always unique, as the root namespace was unique, even if the rest of it is not.

Mosaics are named joining the namespace name with the mosaic name using the ‘:’ symbol. Renting a namespace called nem and a mosaic called xem under it, the mosaic is referenced as nem:xem.

Consider the following restrictions:

  • Mosaic names have a size limit of 64 characters and must be unique under the domain name.
  • Allowed characters are a, b, c, …, z, 0, 1, 2, …, 9, ‘, _ , -.


The public key of the mosaic creator.


The behavior of a mosaic can be customized by a set of properties. Supported properties are:

  • Divisibility: Determines up to what decimal place the mosaic can be divided. Divisibility of 3 means that a mosaic can be divided into smallest parts of 0.001 mosaics. The divisibility must be in the range of 0 and 6.
  • Duration: The number of confirmed blocks we would like to rent our namespace for.
  • Supply: The amount of mosaic in circulation. The creator can specify an initial supply of mosaics when creating the definition. The initial supply must be in the range of 0 and 9,000,000,000.
  • Supply mutable: The creator can choose between a definition that allows a mosaic supply to change at a later point or an immutable supply. In the first case, the creator is only allowed to decrease the supply within the limits of mosaics owned.
  • Transferability: The creator can choose whether the mosaic can be transferred to and from arbitrary accounts, or only allowing him/herself to be the recipient once transferred.

Mosaic supply change transaction

Mosaic supply change transaction is used to assign supply to a mosaic.

Mosaic Id

Combination of namespace name and mosaic name. For example “”.


Could be Increase (0) or Decrease (1).


The amount of supply to increase or decrease.