United States, 6 Cents, Marconi Spark Coil
| Country | United States |
| Year | 1973 |
| Name | United States, 6 Cents, Marconi Spark Coil |
| Denomination | 6 Cents |
| Type of Issue: | Definitive |
| Theme | Science |
| Color | lilac, multicolored |
| Printing Method | lithographed, engraved (Giori press) |
| Printed by: | Bureau of Engraving and Printing, Washington DC |
| Perforation type: | Perforated |
| Tagging | n/a |
| Description | Electronics Progress - Marconi Spark Coil |
