I couldn't find any notes on the character map as found in the Adafruit 1.8" TFT w/Joystick shield, which uses the ST7735 and foundation Adafruit_GFX library. The font is described in Adafruit_GFX/glcdfont.c but I couldn't decipher the values and decided to see them rather than write a program to hash the source file.
I have a working sketch here https://github.com/cacycleworks/st7735_charmap
it lets you page through the character map and has a grid. Left column has the starting number for each row, ex: 0x10. Across the top are the numbers for each column, 0-f. In the sample picture, left arrow quote is 0xae.
Moving the joystick down scrolls down to the next page. (and up moves up)