> For the complete documentation index, see [llms.txt](https://etica.gitbook.io/etica-randomx/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://etica.gitbook.io/etica-randomx/basics/markdown.md).

# Blob

Everything you need to know about the blob

### The Blob in Cryptocurrency Mining

The "blob" is a crucial concept in RandomX mining, serving as the primary input for the hashing function. It's a byte string that contains essential information about the block being mined.

Monero Blob Example: A typical Monero blob might look like this (in hexadecimal):

{% hint style="info" %}
da4670bae10db93a46fad64b14d091189ca<mark style="color:green;">fa19f61674</mark>963f2f2d635b4f2a812685f828da7adb7de554b4090363931bde43a6042eafd6197fbf4866191c9e845ae615393f941f4bb9f92b7ed537c2fb7

Position 39-42bytes <mark style="color:green;">fa19f61674:</mark> Nonce
{% endhint %}

As you can see it's a 76bytes string that is generated by hashing a Monero Block template.

#### Etica Blob Structure:

Etica doesn't generate the blob from a block template but the resulting blob is exactly same format as Monero RandomX blobs. Etica uses a ReservedSpace system to place it direclty in the blob.

Here is an example of an Etica Blob:

{% hint style="info" %}
da4670bae10db93a46fad64b14d091189ca<mark style="color:green;">fa19f61674</mark>963f2f2d635b4f2a812<mark style="color:purple;">685f828da7adb7de</mark>554b4090363931bde43a6042eafd6197fbf4866191c9e845ae615393f941f4bb9f92b7ed537c2fb7

Position 39-42bytes <mark style="color:green;">fa19f61674:</mark> Nonce

Position 55-62bytes <mark style="color:purple;">685f828da7adb7de:</mark> ReservedSpace
{% endhint %}

#### Nonce

When miners receive the blob, their mining software iterates by replacing the bytes at a certain position (it is named the nonceOffset). \
***In Monero and Etica the NonceOffset is at position 39bytes and has a size of 4bytes.***

#### ReservedSpace

In the RandomX system it is important that each miner receives a specific Blob, not all miners mine on the same Blob. In order to generate specific blobs there is a ReservedSpace\
Reserved Space (55-62 bytes):

* 8 bytes reserved for miner-specific data
* This is where the truncated extraNonceHash is inserted

Etica's implementation of RandomX uses a blob structure inspired by Monero but tailored to its own blockchain requirements. Here's a breakdown of the Etica blob: