Help identify what is wrong with my coin 1 1

[Adina73]

Does anyone know what these lines are across my coins? I have many and all different years. 

[Greenstang]

Welcome to the forum

They appear to be roller lines, not uncommon on 70’s cents

[powermad5000]

Hello and welcome to the forum!
 

From what I know, that streaked effect on cents which dates back many years and is referred to as "woody" or "woodgrain effect", is from impurities in the alloy or an alloy that was not properly mixed, and when the bronze or copper was rolled into its final form before blanking, it developed into this stretched pattern that you see on the coin after it is struck. In laymen's terms you are seeing differences in the metal visible as streaks.

[Sandon]

   Assuming that the 95% copper, 5% alloy of which these coins were made was not quite evenly mixed, resulting in these streaks, there is nothing "wrong" with these coins. The Denver mint made billions of cents during each of these years, and their appearance is well within acceptable standards for such mass-produced pieces.

  I'm not satisfied, however, that any or all of these circulated cents contains improperly mixed alloy. Copper and zinc are highly reactive metals, and the streaks could have resulted from commonly encountered environmental factors, such as the coins lying on a damp tabletop.

[Mike Meenderink]

While Sandon may have a theory about "damp table tops" this is patently false. Striations occur as visible metallurgical differentiation on all types of planchets with an improperly mixed alloy content. Pennys, quarters, nickels can all have this appearance if struck on an improperly mixed alloy planchet. Of course, these are very common and only sought after with very pronounced wood grain effects.

[RWB]

Shingles.