It stands for 10 Karat gold plated in 98% of circumstances. I have not yet come across an item using "Plumb" in association with 10 karat and I have not yet come across "kgp" used for "Karat gold plumb". So, sorry, it's just plated.
According to SOWPODS (the combination of Scrabble dictionaries used around the world) there are 1 words with the pattern K-R--G--P. That is, nine letter words with 1st letter K and 3rd letter R and 6th letter G and 9th letter P. In alphabetical order, they are: kirbigrip
R. K. Narayan was born on October 10, 1906.
ballroom
5 = p r k n g a and i are both vowels.
S - p - o - n - g - e - b - o - b s - q - u - a - r - e - p - a - n - t - s p - a - t - r - i - c - k s - t - a - r - r s - q - u - i - d - w - a - r - d t - e - n - t - a - c - l - e - s e - u - g - e - n - e k - r - a - b - s p - l - a - n - k - t - o - n g - a - r - y
upper: F,G,J,L,P,R lower: a,b,d,e,f,g,h,j,k,p,q,r,t,y
K. P. R. Gopalan died in 1997.
P. K. R. Warrier died in 2011.
P. K. R. Warrier was born in 1921.
P=q/r* * * * *The correct answer is P = k*q/r where k is the constant of proportionality.
Project G-e-e-K-e-R- - 1996 Worm 1-10 was released on: USA: 16 November 1996
B (in some fonts), F, G, J, P, Q, R, a, b, d, e, f, g, h, i, j, k, m, n, p, q, r, t, u and y.