Texel Density is how much resolution is on a mesh. It is affected by the texel density set, the UV map and the mesh. More detail in the texture indicates a higher texel density. It is important that the resolution stays consistent throughout the model and objects in a scene. Having one object or a part of a mesh high resolution and the rest low resolution would usually look disjointed.
The texel density of this sword model is consistent and the detail overall in the cracks, metallic appearance and the effect of a light glowing from or against the golden part of the sword. One side of the sword is copied onto the other side to save time but at a glance it looks very visually appealing
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