"This so called Teal blue colour was introduced in early1956 on the Austin Healey Hundred, series BN2. In fact in early January 1956 they seemed to introduce a number of new colours as a bit of an experiment, to see what the public's reaction might be. For example with exterior colours, Spruce Green was dropped and Florida Green was introduced. Carmine Red was dropped and Reno Red was introduced."
"Teal" Blue Interior

"Teal" Blue was not the official factory name for the colour, which was simply called Blue

It is now being used by the Concours Committee to differentiate this colour from the dark Blue, whose official name is also Blue
These "Teal Blue 100 - Sixs had interior components coloured as follows:
- leather seats and armrest facings Teal blue with contrasting piping (but sometimes not)
- vinyl trim panels and vinyl portions of seat backs, rear seats, rear squab panel, armrest    sides matching Teal blue
- carpets dark Navy blue with Teal binding where appropriate
- armacord  in  matching Teal blue with Teal vinyl binding
- top and tonneau cover, dark Navy blue
Meanwhile similar things were tried with some interior colours. The dark green trim was dropped entirely. Likewise the orangey colour we have called Persimmon which went along with the red carpets and armacord binding was dropped, and a new shade of rich crimson red was introduced without any contrasting piping. It seems as far as we can determine that navy blue trim with grey piping was dropped and this Teal Blue shade was introduced.'

Below is  photo of a car with a build date of January 9 1957 taken by Rich at the 2010 Conclave. At present this is the latest date we have for a car with a Teal Blue interior.
If you own a very early Longbridge BN4 and you want to be absolutely   correct and certainly different from the crowd, then you should consider the Teal Blue Interior as this is the correct colour for Healey Blue or Healey Blue and Ivory White cars produced from BN4 introduction up to very early in 1957.

Rich Chrysler explains the background to this interesting and very rare interior colour.
Teal Blue interior of Gold Concours BN2 restored by Rich Chrysler

The photos show similar patterns of fading and colour change to those in the other cars. The sidescreen  bag and the underside of the armrest are probably still quite close to the original colour as they will not have been exposed to sunlight whereas the seat leather has brightened and the seat vinyl has taken on the sludgey grey appearance.

Note also that these seats do
not have white piping. Perhaps this car was even earlier than the two above and had seat covers similar to the BN2s
It would appear that Teal Blue did not last very long in Austin Healey production and the reason was probably that it was impossible to get dyes in that colour which didn't change alarmingly when exposed to sunlight. Certainly the Navy Blue interiors which replaced the Teal show no signs of weathering in this fashion.
Below is a photo of my current car prior to it's restoration. The photo was taken in 1988 but the car had been in this state since 1966. It is car number 30542 built  November 19 1956 and originally Healey Blue and Ivory White per the Heritage Certificate.
Note how the leather has aged completely differently from the vinyl. The leather has  gone a much brighter blue whereas the vinyl has faded to a variety of sludgey bluey/grey colours
The Teal Blue interior is clearly visible and the seats are piped in white similar to the car above, whereas the BN2s had teal piping
Here are some photos from Peter Svilans collection of Teal Blue items from a car which had been brought into Precision Sports Cars for retrimming by Peter