The Grado G1+ had a nude diamond, original called "Grado Type" or "Special Grado Type", later "twin tip" but also "true ellipsoid"
The cantilever was not just straight but a tapered (conical) hardened aluminium cantilever.
There were 3 generations:
During the late F-Series:
Black body, black plate (replacement stylus) with yellow dots (the dots are important!) Black box
Grado F-1+.pdf
During the later G-Series:
Brown body, brown plate (yellow dots): Twin Tip
Last G-Series:
Brown body, brown plate (yellow dots): True Ellipsoid (Same as Grado Type or Twin Tip)
During the F-Series the Grado Type nude stylus of the F1+ and F2+ Grados were hyperelliptical but Grado never used this name but Grado type or Twin Tip
Later he called it True Ellipsoid (until now in 2026 with the Top of the Line modern Grados)
If somebody would find a bonded stylus on a G1+ or G2 (F1+ or F2 as well) then this would be a replacement from a cheaper version
and the colour removed.
If a TAN brown plate then from a GF3e+
If a black plate no dots, then from a F3E+ i.e. elliptical (those were 7x3 nude ellipticals !)