The expressions made from and made of are used differently. When objects consist of material which hasn't been changed in any significant way, made of is used. However, when the material is changed significantly in the process of making of a product, made from is used.
The following examples illustrate the use of made from:
Cream is made from milk.
The earliest canoes were made from tree trunks.
Wine is made from grapes.
These examples illustrate the use of made of:
She wore a beautiful necklace made of expensive silver.
The table is made of glass.
This chair is made of wood.
The expression made from is for a material which was transformed in the process of making the finished product. Grapes aren't visible in wine, so made from is appropriate. When the original material is visible in the finished product, made of is required. Silver is visible in a silver necklace, so made of is used. English makes a distinction that is illustrated by the expressions made from and made of.