My little ultraviolet lamp arrived today: one that is specifically designed to inspect postage stamps. (My pictures below).
Starting in 1969, South Africa began to add phosphorescent frames to stamps from its first definitive series of stamps*. Starting in 1971, the phosphorescent element appeared throughout the paper. It is almost impossible to distinguish between these two types of stamps without the aid of an ultraviolet lamp.
*Definitive series of stamps for the Republic of South Africa. The Union of South Africa became the Republic of South Africa in 1961 when it gained its independence from Great Britain.
Issued 1969-1972
Perf. 14×13½ Photogravure, chalk-surfaced paper, printed with phosphor bands
282 168 ½c New blue, carmine-red and yellow ochre | African Pygmy Kingfisher
[Source: Stanley Gibbons Stamp Catalogue: Commonwealth & British Empire Stamps, 2016 Edition]
Issued 1969-1972
Perf. 13½x14 Photogravure, chalk-surfaced paper, printed with phosphor bands (LEFT, 1969, bands badly misplaced!) and without (RIGHT, 1971)
277 169 1c Rose-red & olive brown | Coral tree flowers
[Source: Stanley Gibbons Stamp Catalogue: Commonwealth & British Empire Stamps, 2016 Edition]
Issued 1969-1972
Perf. 14×13½ Photogravure, chalk-surfaced paper, printed with phosphor bands
284 132 1½c Red brown and light purple | Afrikaner bull
[Source: Stanley Gibbons Stamp Catalogue: Commonwealth & British Empire Stamps, 2016 Edition]
Issued 1969-1972
Perf. 14 Photogravure, chalk-surfaced paper, printed with phosphor bands
285 133 2c Ultramarine and yellow | Pouring gold
[Source: Stanley Gibbons Stamp Catalogue: Commonwealth & British Empire Stamps, 2016 Edition]
Issued 1969-1972
Perf. 14 Photogravure, chalk-surfaced paper, printed with phosphor bands
286 134 2½c Violet and green | Groot Constantia wine estate
[Source: Stanley Gibbons Stamp Catalogue: Commonwealth & British Empire Stamps, 2016 Edition]
Issued 1969-1972
Perf. 14 Photogravure, chalk-surfaced paper, printed with phosphor bands
287 135 3c Red and deep blue |Burchell’s gonolek
[Source: Stanley Gibbons Stamp Catalogue: Commonwealth & British Empire Stamps, 2016 Edition]
Issued 1969-1972
Perf. 14 Photogravure, chalk-surfaced paper, printed with phosphor bands
293 138 10c Brown and pale green | Cape Town Castle gate
[Source: Stanley Gibbons Stamp Catalogue: Commonwealth & British Empire Stamps, 2016 Edition]
Issued 1969-1972
Perf. 14 Photogravure, chalk-surfaced paper, printed with phosphor bands
294 139 20c Turquoise-blue, carmine and brown orange| Secretary Bird
[Source: Stanley Gibbons Stamp Catalogue: Commonwealth & British Empire Stamps, 2016 Edition]