Boyd’s Bible Dictionary:
A metal well known to ancients
(Num. 31:22); evidently dross (Isa. 1:25). Imported from Tarshish (Ezek. 27:12).
“Plumbline, Plummet” From Concise Bible Dictionary:
Plumbline
The simple contrivance of a lump of lead, a stone, or other weight attached to a string, for testing whether a building or other erection is perpendicular. It is used symbolically for the exactness with which judgment was brought upon Israel. Israel had been built up by God as a wall with a plumbline, and with a plumbline it should be destroyed (Amos 7:7-8; compare 2 Kings 21:13; Isa. 28:17). In Zechariah 4:10, although it was a day of small things when the temple was rebuilt, the plummet was in the hands of Zerubbabel, and the Lord of hosts was supporting him.
Plumbline – Ivory – Roman and Greek Art
“Tin” From Concise Bible Dictionary:
Punch Design on Tin Plate
This is the stannum of the ancients, found alloyed with lead, but separated by smelting. It is not known to have been found in Palestine, but would have been early known there and was imported from Tarshish (Num. 31:22; Isa. 1:25; Ezek. 22:18,20; Ezek. 27:12).
Tin Ore
Strong’s Dictionary of Hebrew Words:
Meaning:
from 914; alloy (because removed by smelting); by analogy, tin
KJV Usage:
+ plummet, tin