Al-Baqarah - 2:69

قَالُواْ ادْعُ لَنَا رَبَّكَ يُبَيِّن لَّنَا مَا لَوْنُهَا قَالَ إِنَّهُ يَقُولُ إِنّهَا بَقَرَةٌ صَفْرَاء فَاقِـعٌ لَّوْنُهَا تَسُرُّ النَّاظِرِينَ
[2:69]
They said: Call on your Lord for our sake to make it plain to us what her color is. Musa said: He says, Surely she is a yellow cow; her color is intensely yellow, giving delight to the beholders.
They said: "Beseech on our behalf Thy Lord to make plain to us Her colour." He said: "He says: A fawn-coloured heifer, pure and rich in tone, the admiration of beholders!"
They said: Pray for us unto thy Lord that He make clear to us of what colour she is. (Moses) answered: Lo! He saith: Verily she is a yellow cow. Bright is her colour, gladdening beholders.