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The population of comets hosted by the Oort cloud is heterogeneous. Moststudies in this area focused on highly active objects, those with smallperihelion distances or examples of objects with peculiar physical propertiesand/or unusual chemical compositions. This may have produced a biased sample ofOort cloud comets in which the most common objects may be rare, particularlythose with perihelia well beyond the orbit of the Earth. Within this context,the known Oort cloud comets may not be representative of the full sample. Here,we study the spectral properties in the visible region and the cometaryactivity of Comet C/2018 F4 (PANSTARRS). We also explore its orbital evolutionwith the aim of understanding its origin within the context of known minorbodies moving along nearly parabolic or hyperbolic paths. We presentobservations obtained with the 10.4 m Gran Telescopio Canarias (GTC), derivethe spectral class and visible slope of C/2018 F4 and characterise its level ofcometary activity. Direct N-body simulations are carried out to explore itsorbital evolution. The absolute magnitude of C/2018 F4 is Hr=13.62+/-0.04.Assuming a pV=0.04 its diameter is D<10.4 km. The object presents a conspicuouscoma, with a level of activity comparable to those of other comets observed atsimilar heliocentric distances. Comet C/2018 F4 has a visible spectrumconsistent with that of an X-type asteroid, and has a spectral slopeS'=4.0+/-1.0 %/1000\AA and no evidence of hydration. The spectrum matches thoseof well-studied primitive asteroids and comets. The analysis of its dynamicalevolution prior to discovery suggests that C/2018 F4 is not of extrasolarorigin. Although the present-day heliocentric orbit of C/2018 F4 is slightlyhyperbolic, its observational properties and past orbital evolution areconsistent with those of a dynamically old comet with an origin in the Oortcloud.

Spectroscopic and dynamical properties of comet C/2018 F4, likely a true average former member of the Oort cloud