Depending on your prospecting skill, you will receive different amounts of information from the shard. Nearby ores will appear as traces every few lines. The strength of the traces shows the distance from the tile the shard originated from, to the tile with the ore vein. The level of your prospecting skill will determine the strength of the traces you can detect.
The four six different strengths:
*'''"Traces"''' - Shows for ore that is 1 tile away. Unlocked with Analyse at prospecting level 20.
*'''"Slight traces"''' - Shows for ore that is 2 tiles away. Unlocked with Analyse at prospecting level 20.