PHILIPS COSMOGOLD 65 and 140W SON lamps

Here you can see two lamps that never ade into the mass marked, the Philips CosmoGold 60W and 140W compact high pressure sodium lamps.
During the mid 2000s Philips caught new concepts for street lighting. With traditional clear lamps fixtures had to use different reflectors for MH and HPS lamps for maximum efficiency. This could be overcome by using diffuse elliptic bulbs, but these did not allow very precise optics for the hid lamps due to the large lit surface.
Philips launched their very popular cosmopolis white lamp with pgz12 base. These were very compact CMH lamps designed for street lighting. They were intended to run on property ballast in 45W, 60W, 90W and 140W., with an usual low ignition voltage for CMH lamps of just 2.3kV. Due to their small size an crisp white light these lamps become very popular.
However these lamps have an mostly unknown brother: The Cosmal gold lamp. The idea was the similar: A very compact HPS lamp in the same factor as the CPO MH lamp. The arc tube should be similar enough in order to allow for the same optics to be used. However these lamps never caught on and would never reach further then trials.

In order to allow for compact arc tubes the lamp voltage had to be reduced. This led ultimately to these lamp not being interchangeable with the CPO MH lamps requiring their own property ballast. The effiency is notably better then with standard son lamps however the CR is decreased. Life expectancy was approx the same while offering better lumen maintenance.

However the lamps never become popular likely due to normal HPS lamps being already clear and allowing a good optical control. Likely the benefits did not justify the risk of using a property lamp in a more expensive system.