Australia Antarctic Territory #L14-L17 15c to 50c Scenes, 1966-1973 Decimal Definitive Issue, A Specialized Lot of 7 VFNH Stamps
A VFNH group of 7 stamps, comprising the 15c through 50c stamps from the 1966-1973 decimal definitive issue, including many different unlisted paper and ink varieties, and differences in the strength of the Helecon coating on the paper.
The Australian equivalent of tagging is called Helecon, which is a chemical in the zinc sulphide group that fluoresces orange-red under long-wave UV light. The very first stamp to be issued with Helecon coating applied to the paper was the 11d Rabbit Bandicoot from the 1958-1964 definitive issue. Later, the 5d orange-red Queen Elizabeth II stamp from the 1963-1966 issue was issued with the Helecon incorporated into the ink. By the end of 1965 all stamps issued had Helecon applied to the paper. On this issue, most stamps are found with the paper impregnated with Helecon, so that it appears greyish white from a distance under UV, but under magnification, tiny orange-red dots can be seen on the surface of the paper.
The orange inks on the 10c, 15c, 20c and 50c all fluoresce bright orange under UV.
The comparison picture shows some of the differences that can be found on this issue. The papers appear similar from the front, but from the back, it is clear that the fluorescence levels differ wildly from dull to high fluorescent.
Scott lists the basic stamps at $40.25 for VFNH. The stamps here grade between 75 and 84.